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Neuwirth LS, Emenike BU. Comment on "Neurotoxicity and Outcomes from Developmental Lead Exposure: Persistent or Permanent?". ENVIRONMENTAL HEALTH PERSPECTIVES 2024; 132:48001. [PMID: 38607984 PMCID: PMC11014073 DOI: 10.1289/ehp14809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Accepted: 03/20/2024] [Indexed: 04/14/2024]
Affiliation(s)
- Lorenz S. Neuwirth
- Department of Psychology, State University of New York at Old Westbury (SUNY Old Westbury), Old Westbury, New York, USA
- SUNY Neuroscience Research Institute, SUNY Old Westbury, Old Westbury, New York, USA
| | - Bright U. Emenike
- Department of Chemistry and Physics, SUNY Old Westbury, Old Westbury, New York, USA
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2
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Wylie AC, Short SJ, Fry RC, Mills-Koonce WR, Propper CB. Maternal prenatal lead levels and neonatal brain volumes: Testing moderations by maternal depressive symptoms and family income. Neurotoxicol Teratol 2024; 102:107322. [PMID: 38244816 PMCID: PMC10990786 DOI: 10.1016/j.ntt.2024.107322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 01/17/2024] [Accepted: 01/17/2024] [Indexed: 01/22/2024]
Abstract
There is considerable evidence that prenatal lead exposure is detrimental to child cognitive and socio-emotional development. Further evidence suggests that the effects of prenatal lead on developmental outcomes may be conditional upon exposure to social stressors, such as maternal depression and low socioeconomic status. However, no studies have examined associations between these co-occurring stressors during pregnancy and neonatal brain volumes. Leveraging a sample of 101 mother-infant dyads followed beginning in mid-pregnancy, we examined the main effects of prenatal urinary lead levels on neonatal lateralized brain volumes (left and right hippocampus, amygdala, cerebellum, frontal lobes) and total gray matter. We additionally tested for moderations between lead and depressive symptoms and between lead and family income relative to the federal poverty level (FPL) on the same neurodevelopmental outcomes. Analyses of main effects indicated that prenatal lead was significantly (ps < 0.05) associated with reduced right and left amygdala volumes (βs = -0.23- -0.20). The testing and probing of cross-product interaction terms using simple slopes indicated that the negative effect of lead on the left amygdala was conditional upon mothers having low depressive symptoms or high income relative to the FPL. We interpret the results in the context of trajectories of prenatal and postnatal brain development and susceptibility to low levels of prenatal lead in the context of other social stressors.
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Affiliation(s)
- Amanda C Wylie
- Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, United States; Frank Porter Graham Child Development Institute, University of North Carolina at Chapel Hill, United States.
| | - Sarah J Short
- Department of Educational Psychology, University of Wisconsin-Madison, United States; Center for Healthy Minds, University of Wisconsin-Madison, United States
| | - Rebecca C Fry
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, United States; Institute for Environmental Health Solutions, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, United States
| | - W Roger Mills-Koonce
- School of Education, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Cathi B Propper
- Frank Porter Graham Child Development Institute, University of North Carolina at Chapel Hill, United States; School of Nursing, University of North Carolina at Chapel Hill, United States
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Park HR, Azzara D, Cohen ED, Boomhower SR, Diwadkar AR, Himes BE, O'Reilly MA, Lu Q. Identification of novel NRF2-dependent genes as regulators of lead and arsenic toxicity in neural progenitor cells. JOURNAL OF HAZARDOUS MATERIALS 2024; 463:132906. [PMID: 37939567 PMCID: PMC10842917 DOI: 10.1016/j.jhazmat.2023.132906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 10/29/2023] [Accepted: 10/30/2023] [Indexed: 11/10/2023]
Abstract
Lead (Pb) and arsenic (As) are prevalent metal contaminants in the environment. Exposures to these metals are associated with impaired neuronal functions and adverse effects on neurodevelopment in children. However, the molecular mechanisms by which Pb and As impair neuronal functions remain poorly understood. Here, we identified F2RL2, TRIM16L, and PANX2 as novel targets of Nuclear factor erythroid 2-related factor 2 (NRF2)-the master transcriptional factor for the oxidative stress response-that are commonly upregulated with both Pb and As in human neural progenitor cells (NPCs). Using a ChIP (Chromatin immunoprecipitation)-qPCR assay, we showed that NRF2 directly binds to the promoter region of F2RL2, TRIM16L, and PANX2 to regulate expression of these genes. We demonstrated that F2RL2, PANX2, and TRIM16L have differential effects on cell death, proliferation, and differentiation of NPCs in both the presence and absence of metal exposures, highlighting their roles in regulating NPC function. Furthermore, the analyses of the transcriptomic data on NPCs derived from autism spectrum disorder (ASD) patients revealed that dysregulation of F2RL2, TRIM16L, and PANX2 was associated with ASD genetic backgrounds and ASD risk genes. Our findings revealed that Pb and As induce a shared NRF2-dependent transcriptional response in NPCs and identified novel genes regulating NPC function. While further in vivo studies are warranted, this study provides a novel mechanism linking metal exposures to NPC function and identifies potential genes of interest in the context of neurodevelopment.
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Affiliation(s)
- Hae-Ryung Park
- Department of Environmental Medicine, School of Medicine and Dentistry, University of Rochester, Rochester, NY, USA.
| | - David Azzara
- Department of Environmental Medicine, School of Medicine and Dentistry, University of Rochester, Rochester, NY, USA
| | - Ethan D Cohen
- Department of Pediatrics, School of Medicine and Dentistry, University of Rochester, Rochester, NY, USA
| | - Steven R Boomhower
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Avantika R Diwadkar
- Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania, Philadelphia, PA, USA
| | - Blanca E Himes
- Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania, Philadelphia, PA, USA
| | - Michael A O'Reilly
- Department of Pediatrics, School of Medicine and Dentistry, University of Rochester, Rochester, NY, USA
| | - Quan Lu
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
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Xia Y, Li Z, Wang C, Zhang X, Li J, Zhou Q, Yang J, Chen Q, Meng X, Wang J. Dynamic alterations of locomotor activity and the microbiota in zebrafish larvae with low concentrations of lead exposure. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:2042-2052. [PMID: 38051486 DOI: 10.1007/s11356-023-31279-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 11/24/2023] [Indexed: 12/07/2023]
Abstract
Lead (Pb) is a ubiquitous heavy metal associated with developmental and behavioral disorders. The establishment of pioneer microbiota overlaps with the development of the brain during early life, and Pb-induced developmental neurotoxicity may be partially caused by early-life microbiota dysbiosis. This study investigated the locomotor activity and the microbiota in developing zebrafish at multiple developmental time points (five days post fertilization [5 dpf], 6 dpf, and 7 dpf) under exposure to low concentrations of lead (0.05 mg/L). Time-dependent reductions in the number of activities and the average movement distance of larvae compared to the control were observed following Pb exposure. Furthermore, Pb exposure significantly altered the composition of the gut microbiota of zebrafish larvae. At the phylum level, the abundance of Proteobacteria decreased from 5 to 7 dpf, while that of Actinobacteria increased in the control groups. At the class level, the proportion of Alphaproteobacteria decreased, while that of Actinobacteria increased in the control groups. Notably, all showed the opposite trend in Pb groups. A correlation analysis between indices of locomotor activity and microbial communities revealed genus-level features that were clearly linked to the neurobehavioral performance of zebrafish. Seven genera were significantly correlated with the two performance indicators of the locomotion analysis, namely Rhodococcus, Deinococcus, Bacillus, Bosea, Bradyrhizobium, Staphylococcus, and Rhizobium. Rhizobium was dominant in zebrafish and increased in the Pb groups in a time-dependent manner. In addition, the expression levels of bdnf, trkb1, trkb2, and p75ntr changed in zebrafish from 5 to 7 dpf under Pb exposure. Collectively, these results suggest that Pb-induced neurotoxicity could potentially be treated by targeting the gut microbiota.
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Affiliation(s)
- Yuan Xia
- School of Public Health, Guangdong Pharmaceutical University, Jianghaidadao, Guangzhou, 283, Guangdong, China
| | - Ziyi Li
- School of Public Health, Guangdong Pharmaceutical University, Jianghaidadao, Guangzhou, 283, Guangdong, China
| | - Chunyu Wang
- School of Public Health, Guangdong Pharmaceutical University, Jianghaidadao, Guangzhou, 283, Guangdong, China
| | - Xiaoshun Zhang
- Department of Occupational Health and Occupational Medicine, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, Guangdong, China
| | - Junyi Li
- School of Public Health, Guangdong Pharmaceutical University, Jianghaidadao, Guangzhou, 283, Guangdong, China
| | - Qin Zhou
- Department of Occupational Health and Occupational Medicine, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, Guangdong, China
| | - Jian Yang
- School of Public Health, Guangdong Pharmaceutical University, Jianghaidadao, Guangzhou, 283, Guangdong, China
| | - Qingsong Chen
- School of Public Health, Guangdong Pharmaceutical University, Jianghaidadao, Guangzhou, 283, Guangdong, China
| | - Xiaojing Meng
- Department of Occupational Health and Occupational Medicine, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, Guangdong, China
| | - Junyi Wang
- School of Public Health, Guangdong Pharmaceutical University, Jianghaidadao, Guangzhou, 283, Guangdong, China.
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5
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Bjørklund G, Tippairote T, Hangan T, Chirumbolo S, Peana M. Early-Life Lead Exposure: Risks and Neurotoxic Consequences. Curr Med Chem 2024; 31:1620-1633. [PMID: 37031386 DOI: 10.2174/0929867330666230409135310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Revised: 02/10/2023] [Accepted: 02/16/2023] [Indexed: 04/10/2023]
Abstract
BACKGROUND Lead (Pb) does not have any biological function in a human, and it is likely no safe level of Pb in the human body. The Pb exposure impacts are a global concern for their potential neurotoxic consequences. Despite decreasing both the environmental Pb levels and the average blood Pb levels in the survey populations, the lifetime redistribution from the tissues-stored Pb still poses neurotoxic risks from the low-level exposure in later life. The growing fetus and children hold their innate high-susceptible to these Pb-induced neurodevelopmental and neurobehavioral effects. OBJECTIVE This article aims to evaluate cumulative studies and insights on the topic of Pb neurotoxicology while assessing the emerging trends in the field. RESULTS The Pb-induced neurochemical and neuro-immunological mechanisms are likely responsible for the high-level Pb exposure with the neurodevelopmental and neurobehavioral impacts at the initial stages. Early-life Pb exposure can still produce neurodegenerative consequences in later life due to the altered epigenetic imprints and the ongoing endogenous Pb exposure. Several mechanisms contribute to the Pb-induced neurotoxic impacts, including the direct neurochemical effects, the induction of oxidative stress and inflammation through immunologic activations, and epigenetic alterations. Furthermore, the individual nutritional status, such as macro-, micro-, or antioxidant nutrients, can significantly influence the neurotoxic impacts even at low-level exposure to Pb. CONCLUSION The prevention of early-life Pb exposure is, therefore, the critical determinant for alleviating various Pb-induced neurotoxic impacts across the different age groups.
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Affiliation(s)
- Geir Bjørklund
- Council for Nutritional and Environmental Medicine (CONEM), Toften 24, Mo i Rana, 8610, Norway
| | - Torsak Tippairote
- Department of Nutritional and Environmental Medicine, HP Medical Center, Bangkok 10540, Thailand
| | - Tony Hangan
- Faculty of Medicine, Ovidius University of Constanta, Constanta, 900470, Romania
| | - Salvatore Chirumbolo
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, 37134, Italy
- CONEM Scientific Secretary, Strada Le Grazie 9, 37134, Verona, Italy
| | - Massimiliano Peana
- Department of Chemical, Physical, Mathematical and Natural Sciences, University of Sassari, Via Vienna 2, Sassari, 07100, Italy
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Li D, Huang C, Liu Z, Ai S, Wang HL. Decreased expression of Chrna4 by METTL3-mediated m6A modification participates in BPA-induced spatial memory deficit. ENVIRONMENTAL RESEARCH 2023; 236:116717. [PMID: 37495067 DOI: 10.1016/j.envres.2023.116717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 07/18/2023] [Accepted: 07/19/2023] [Indexed: 07/28/2023]
Abstract
Bisphenol A (BPA), a widely used endocrine disruptor, has been implicated in cognitive impairment via epigenetic machinery. N6-methyl adenosine (m6A) has recently emerged as a new epigenetic factor that influences cognition, but the role of m6A in BPA induced cognitive deficits has not been explored yet. In this study, we found increased global m6A abundance accompanied with elevated expression of methyltransferase-like 3 (METTL3) in hippocampal neurons following BPA exposure. Inhibition of METTL3 activity by selective METTL3 inhibitor 2457 (STM) in cultured neurons abolished BPA induced m6A upregulation and abnormal synaptic transmission. Additionally, knockdown of METTL3 in hippocampus abrogated BPA induced learning and memory deficit in rats. Further study showed that m6A modification was enriched in mRNA of cholinergic receptor nicotinic alpha 4 subunit (Chrna4). Inhibition of METTL3 either by STM or shRNA restored BPA induced downregulation of Chrna4, suggesting that Chrna4 may be a potential target involved in BPA induced neurotoxicity that modified by m6A. Collectively, our findings demonstrated that METTL3 mediated m6A modification was involved in BPA induced cognitive deficit with Chrna4 as a potential target, which enriched our understanding of the role of epigenetics (RNA modifications) in BPA induced neurotoxicity and provided new insights into BPA or its substitutes induced damages in other organs.
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Affiliation(s)
- Danyang Li
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Chengqing Huang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Zhihua Liu
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Shu Ai
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Hui-Li Wang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China.
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Guilarte TR. Invited Perspective: Challenging the Dogma of Lead Neurotoxicity. ENVIRONMENTAL HEALTH PERSPECTIVES 2023; 131:81306. [PMID: 37639478 PMCID: PMC10461787 DOI: 10.1289/ehp13184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 07/21/2023] [Accepted: 08/02/2023] [Indexed: 08/31/2023]
Affiliation(s)
- Tomás R. Guilarte
- Robert Stempel College of Public Health & Social Work, Florida International University, Miami, Florida, USA
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8
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Ai S, Li D, Gu X, Xu Y, Wang Y, Wang HL, Chen XT. Profile of N6-methyladenosine of Pb-exposed neurons presents epitranscriptomic alterations in PI3K-AKT pathway-associated genes. Food Chem Toxicol 2023:113821. [PMID: 37269892 DOI: 10.1016/j.fct.2023.113821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 04/21/2023] [Accepted: 05/08/2023] [Indexed: 06/05/2023]
Abstract
Lead (Pb) is a pervasive heavy metal with multi-organ toxicity. However, the molecular mechanisms of Pb-induced neurotoxicity are not fully understood. The dynamics of N6-methylademine (m6A) is an emerging regulatory mechanism for gene expression, which is closely related to nervous system diseases. To elucidate the association between m6A modification and Pb-mediated neurotoxicity, primary hippocampal neurons exposed to 5 μM Pb for 48 h were used as the paradigm neurotoxic model in this study. According to the results, Pb exposure reprogrammed the transcription spectrum. Simultaneously, Pb exposure remodeled the transcriptome-wide distribution of m6A while disrupting the overall level of m6A in cellular transcripts. United analysis of MeRIP-Seq and RNA-Seq was applied to further identify the core genes whose expression levels are regulated by m6A in the process of lead-induced nerve injury. GO and KEGG analysis unveiled that the modified transcripts were overrepresented by the PI3K-AKT pathway. Mechanically, we elucidated the regulatory role of the methyltransferase like3 (METTL3) in the process of lead-induced neurotoxicity and the downregulation of the PI3K-AKT pathway. In conclusion, our novel findings shed new light on the functional roles of m6A modification in the expressional alternations of downstream transcripts caused by lead, providing an innovative molecular basis to explain Pb neurotoxicity.
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Affiliation(s)
- Shu Ai
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui, PR China
| | - Danyang Li
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui, PR China
| | - Xiaozhen Gu
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui, PR China
| | - Yi Xu
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui, PR China
| | - Yi Wang
- School of Pharmacy, Anhui Medical University, Hefei, Anhui, PR China
| | - Hui-Li Wang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui, PR China.
| | - Xiang-Tao Chen
- School of Pharmacy, Anhui Medical University, Hefei, Anhui, PR China.
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Wang T, Guan RL, Zou YF, Zheng G, Shen XF, Cao ZP, Yang RH, Liu MC, Du KJ, Li XH, Aschner M, Zhao MG, Chen JY, Luo WJ. MiR-130/SNAP-25 axis regulate presynaptic alteration in anterior cingulate cortex involved in lead induced attention deficits. JOURNAL OF HAZARDOUS MATERIALS 2023; 443:130249. [PMID: 36332276 DOI: 10.1016/j.jhazmat.2022.130249] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 10/18/2022] [Accepted: 10/21/2022] [Indexed: 06/16/2023]
Abstract
Brain volume decrease in the anterior cingulate cortex (ACC) after lead (Pb) exposure has been linked to persistent impairment of attention behavior. However, the precise structural change and molecular mechanism for the Pb-induced ACC alteration and its contribution to inattention have yet to be fully characterized. The present study determined the role of miRNA regulated synaptic structural and functional impairment in the ACC and its relationship to attention deficit disorder in Pb exposed mice. Results showed that Pb exposure induced presynaptic impairment and structural alterations in the ACC. Furthermore, we screened for critical miRNA targets responsible for the synaptic alteration. We found that miR-130, which regulates presynaptic vesicle releasing protein SNAP-25, was responsible for the presynaptic impairment in the ACC and attention deficits in mice. Blocking miR-130 function reversed the Pb-induced decrease in the expression of its presynaptic target SNAP-25, leading to the redistribution of presynaptic vesicles, as well as improved presynaptic function and attention in Pb exposed mice. We report, for the first time, that miR-130 regulating SNAP-25 mediates Pb-induced presynaptic structural and functional impairment in the ACC along with attention deficit disorder in mice.
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Affiliation(s)
- Tao Wang
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China.
| | - Rui-Li Guan
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Yun-Feng Zou
- Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning 530021, China
| | - Gang Zheng
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Xue-Feng Shen
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Zi-Peng Cao
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Rui-Hua Yang
- Department of Nutrition & Food Hygiene and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Ming-Chao Liu
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Ke-Jun Du
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Xue-Hang Li
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Ming-Gao Zhao
- Precision Pharmacy & Drug Development Center, Department of Pharmacy, Tangdu Hospital, Fourth Military Medical University, Xi'an 710032, China.
| | - Jing Yuan Chen
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China.
| | - Wen-Jing Luo
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China.
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Liu M, Liu R, Wang R, Ba Y, Yu F, Deng Q, Huang H. Lead-induced neurodevelopmental lesion and epigenetic landscape: Implication in neurological disorders. J Appl Toxicol 2022. [PMID: 36433892 DOI: 10.1002/jat.4419] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 11/20/2022] [Accepted: 11/20/2022] [Indexed: 11/27/2022]
Abstract
Lead (Pb) was implicated in multiple genotoxic, neuroepigenotoxic, and chromosomal-toxic mechanisms and interacted with varying synaptic plasticity pathways, likely underpinning previous reports of links between Pb and cognitive impairment. Epigenetic changes have emerged as a promising biomarker for neurological disorders, including cognitive disorders, Alzheimer's disease (AD), and Parkinson's disease (PD). In the present review, special attention is paid to neural epigenetic features and mechanisms that can alter gene expression patterns upon environmental Pb exposure in rodents, primates, and zebrafish. Epigenetic modifications have also been discussed in population studies and cell experiment. Further, we explore growing evidence of potential linkage between Pb-induced disruption of regulatory pathway and neurodevelopmental and neurological disorders both in vivo and in vitro. These findings uncover how epigenome in neurons facilitates the development and function of the brain in response to Pb insult.
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Affiliation(s)
- Mengchen Liu
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan province, 450001, China
| | - Rundong Liu
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan province, 450001, China
| | - Ruike Wang
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan province, 450001, China
| | - Yue Ba
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan province, 450001, China
| | - Fangfang Yu
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan province, 450001, China
| | - Qihong Deng
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan province, 450001, China
| | - Hui Huang
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan province, 450001, China
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11
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Zhu K, Liu Q, Xie X, Jiang Q, Feng Y, Xiao P, Wu X, Song R. The combined effect between BDNF genetic polymorphisms and exposure to metals on the risk of Chinese dyslexia. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 308:119640. [PMID: 35718045 DOI: 10.1016/j.envpol.2022.119640] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 06/05/2022] [Accepted: 06/13/2022] [Indexed: 06/15/2023]
Abstract
BDNF gene has been implicated in the development of cognition and language. Meanwhile, exposure to metals might interact with BDNF gene to increase the risk of neurodevelopmental disorders. The present study aimed to explore the association between BDNF genetic polymorphisms and dyslexic risk and examine whether BDNF polymorphisms would interact with metal exposures, jointly contributing to dyslexia. Among a case-control study composed of 238 children with dyslexia and 228 healthy controls, the BDNF genetic polymorphisms were genotyped by the Sequenom MassARRAY system, and the exposure to eight metals, such as lead (Pb), mercury (Hg) and copper (Cu), were measured using an inductively coupled plasma-mass spectrometer (ICP-MS). Multivariable logistic regression models were used to assess the adjusted odds ratios (ORs) and 95% confidence interval (CI) of dyslexia. After multivariate adjustment, significant associations of dyslexic risk with rs6265 polymorphisms of the BDNF gene were observed (OR = 1.99; 95% CI: 1.15-3.44). Furthermore, exposure to Cu could interact with rs6265 to increase the risk of dyslexia (P interaction = 0.045). High-Cu children with the rs6265 TT genotype were more likely to have dyslexia compared with low-Cu children carrying CC + CT genotypes (OR = 3.19; 95% CI: 1.38-7.39). The findings of this study suggested that the polymorphism of rs6265 in BDNF gene could interact with Cu exposure to increase the occurrence of dyslexia.
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Affiliation(s)
- Kaiheng Zhu
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qi Liu
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xinyan Xie
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qi Jiang
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yanan Feng
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Pei Xiao
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaoqian Wu
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ranran Song
- Department of Maternal and Child Health and MOE (Ministry of Education) Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
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12
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Lauvås AJ, Lislien M, Holme JA, Dirven H, Paulsen RE, Alm IM, Andersen JM, Skarpen E, Sørensen V, Macko P, Pistollato F, Duale N, Myhre O. Developmental neurotoxicity of acrylamide and its metabolite glycidamide in a human mixed culture of neurons and astrocytes undergoing differentiation in concentrations relevant for human exposure. Neurotoxicology 2022; 92:33-48. [PMID: 35835329 DOI: 10.1016/j.neuro.2022.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 06/29/2022] [Accepted: 07/08/2022] [Indexed: 11/19/2022]
Abstract
Neural stem cells (NSCs) derived from human induced pluripotent stem cells were used to investigate effects of exposure to the food contaminant acrylamide (AA) and its main metabolite glycidamide (GA) on key neurodevelopmental processes. Diet is an important source of human AA exposure for pregnant women, and AA is known to pass the placenta and the newborn may also be exposed through breast feeding after birth. The NSCs were exposed to AA and GA (1 ×10-8 - 3 ×10-3 M) under 7 days of proliferation and up to 28 days of differentiation towards a mixed culture of neurons and astrocytes. Effects on cell viability was measured using Alamar Blue™ cell viability assay, alterations in gene expression were assessed using real time PCR and RNA sequencing, and protein levels were quantified using immunocytochemistry and high content imaging. Effects of AA and GA on neurodevelopmental processes were evaluated using endpoints linked to common key events identified in the existing developmental neurotoxicity adverse outcome pathways (AOPs). Our results suggest that AA and GA at low concentrations (1 ×10-7 - 1 ×10-8 M) increased cell viability and markers of proliferation both in proliferating NSCs (7 days) and in maturing neurons after 14-28 days of differentiation. IC50 for cell death of AA and GA was 5.2 × 10-3 M and 5.8 × 10-4 M, respectively, showing about ten times higher potency for GA. Increased expression of brain derived neurotrophic factor (BDNF) concomitant with decreased synaptogenesis were observed for GA exposure (10-7 M) only at later differentiation stages, and an increased number of astrocytes (up to 3-fold) at 14 and 21 days of differentiation. Also, AA exposure gave tendency towards decreased differentiation (increased percent Nestin positive cells). After 28 days, neurite branch points and number of neurites per neuron measured by microtubule-associated protein 2 (Map2) staining decreased, while the same neurite features measured by βIII-Tubulin increased, indicating perturbation of neuronal differentiation and maturation.
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Affiliation(s)
- Anna Jacobsen Lauvås
- Department of Chemical Toxicology, Norwegian Institute of Public Health (NIPH), Oslo, Norway
| | - Malene Lislien
- Department of Chemical Toxicology, Norwegian Institute of Public Health (NIPH), Oslo, Norway
| | - Jørn Andreas Holme
- Department of Chemical Toxicology, Norwegian Institute of Public Health (NIPH), Oslo, Norway
| | - Hubert Dirven
- Department of Chemical Toxicology, Norwegian Institute of Public Health (NIPH), Oslo, Norway
| | - Ragnhild Elisabeth Paulsen
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, Norway
| | - Inger Margit Alm
- Department of Chemical Toxicology, Norwegian Institute of Public Health (NIPH), Oslo, Norway
| | - Jill Mari Andersen
- Department of Chemical Toxicology, Norwegian Institute of Public Health (NIPH), Oslo, Norway
| | - Ellen Skarpen
- Core Facility for Advanced Light Microscopy, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Vigdis Sørensen
- Core Facility for Advanced Light Microscopy, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Peter Macko
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | | | - Nur Duale
- Department of Chemical Toxicology, Norwegian Institute of Public Health (NIPH), Oslo, Norway
| | - Oddvar Myhre
- Department of Chemical Toxicology, Norwegian Institute of Public Health (NIPH), Oslo, Norway.
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13
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Cuomo D, Foster MJ, Threadgill D. Systemic review of genetic and epigenetic factors underlying differential toxicity to environmental lead (Pb) exposure. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:35583-35598. [PMID: 35244845 PMCID: PMC9893814 DOI: 10.1007/s11356-022-19333-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 02/17/2022] [Indexed: 05/03/2023]
Abstract
Lead (Pb) poisoning is a major public health concern in environmental justice communities of the USA and in many developing countries. There is no identified safety threshold for lead in blood, as low-level Pb exposures can lead to severe toxicity in highly susceptible individuals and late onset of diseases from early-life exposure. However, identifying "susceptibility genes" or "early exposure biomarkers" remains challenging in human populations. There is a considerable variation in susceptibility to harmful effects from Pb exposure in the general population, likely due to the complex interplay of genetic and/or epigenetic factors. This systematic review summarizes current state of knowledge on the role of genetic and epigenetic factors in determining individual susceptibility in response to environmental Pb exposure in humans and rodents. Although a number of common genetic and epigenetic factors have been identified, the reviewed studies, which link these factors to various adverse health outcomes following Pb exposure, have provided somewhat inconsistent evidence of main health effects. Acknowledging the compelling need for new approaches could guide us to better characterize individual responses, predict potential adverse outcomes, and identify accurate and usable biomarkers for Pb exposure to improve mitigation therapies to reduce future adverse health outcomes of Pb exposure.
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Affiliation(s)
- Danila Cuomo
- Department of Molecular and Cellular Medicine, Texas A&M University, College Station, TX, USA.
| | - Margaret J Foster
- Medical Sciences Library, Texas A&M University, College Station, TX, USA
| | - David Threadgill
- Department of Molecular and Cellular Medicine and Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA.
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14
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Czarzasta K, Bogacki-Rychlik W, Segiet-Swiecicka A, Kruszewska J, Malik J, Skital V, Kasarello K, Wrzesien R, Bialy M, Sajdel-Sulkowska EM. Gender differences in short- vs. long-term impact of maternal depression following pre-gestational chronic mild stress. Exp Neurol 2022; 353:114059. [DOI: 10.1016/j.expneurol.2022.114059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 03/24/2022] [Accepted: 03/27/2022] [Indexed: 11/04/2022]
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15
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Tasin FR, Ahmed A, Halder D, Mandal C. On-going consequences of in utero exposure of Pb: An epigenetic perspective. J Appl Toxicol 2022; 42:1553-1569. [PMID: 35023172 DOI: 10.1002/jat.4287] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 12/23/2021] [Accepted: 01/01/2022] [Indexed: 11/08/2022]
Abstract
Epigenetic modifications by toxic heavy metals are one of the intensively investigated fields of modern genomic research. Among a diverse group of heavy metals, lead (Pb) is an extensively distributed toxicant causing an immense number of abnormalities in the developing fetus via a wide variety of epigenetic changes. As a divalent cation, Pb can readily cross the placental membrane and the fetal blood brain barrier leading to far-reaching alterations in DNA methylation patterns, histone protein modifications and micro-RNA expression. Over recent years, several human cohorts and animal model studies have documented hyper- and hypo-methylation of developmental genes along with altered DNA methyl-transferase expression by in utero Pb exposure in a dose-, duration- and sex-dependent manner. Modifications in the expression of specific histone acetyltransferase enzymes along with histone acetylation and methylation levels have been reported in rodent and murine models. Apart from these, down-regulation and up-regulation of certain microRNAs crucial for fetal development have been shown to be associated with in utero Pb exposure in human placenta samples. All these modifications in the developing fetus during the prenatal and perinatal stages reportedly caused severe abnormalities in early or adult age, such as - impaired growth, obesity, autism, diabetes, cardiovascular diseases, risks of cancer development and Alzheimer's disease. In this review, currently available information on Pb-mediated alterations in the fetal epigenome is summarized. Further research on Pb-induced epigenome modification will help to understand the mechanisms in detail and will enable us to formulate safety guidelines for pregnant women and developing children.
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Affiliation(s)
- Fahim Rejanur Tasin
- Biotechnology and Genetic Engineering Discipline, Khulna University, Khulna, Bangladesh
| | - Asif Ahmed
- Biotechnology and Genetic Engineering Discipline, Khulna University, Khulna, Bangladesh
| | - Debasish Halder
- Rare Disease research center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Republic of Korea
| | - Chanchal Mandal
- Biotechnology and Genetic Engineering Discipline, Khulna University, Khulna, Bangladesh
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16
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Lead (Pb) and neurodevelopment: A review on exposure and biomarkers of effect (BDNF, HDL) and susceptibility. Int J Hyg Environ Health 2021; 238:113855. [PMID: 34655857 DOI: 10.1016/j.ijheh.2021.113855] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 09/29/2021] [Accepted: 10/01/2021] [Indexed: 12/13/2022]
Abstract
Lead (Pb) is a ubiquitous environmental pollutant and a potent toxic compound. Humans are exposed to Pb through inhalation, ingestion, and skin contact via food, water, tobacco smoke, air, dust, and soil. Pb accumulates in bones, brain, liver and kidney. Fetal exposure occurs via transplacental transmission. The most critical health effects are developmental neurotoxicity in infants and cardiovascular effects and nephrotoxicity in adults. Pb exposure has been steadily decreasing over the past decades, but there are few recent exposure data from the general European population; moreover, no safe Pb limit has been set. Sensitive biomarkers of exposure, effect and susceptibility, that reliably and timely indicate Pb-associated toxicity are required to assess human exposure-health relationships in a situation of low to moderate exposure. Therefore, a systematic literature review based on PubMed entries published before July 2019 that addressed Pb exposure and biomarkers of effect and susceptibility, neurodevelopmental toxicity, epigenetic modifications, and transcriptomics was conducted. Finally included were 58 original papers on Pb exposure and 17 studies on biomarkers. The biomarkers that are linked to Pb exposure and neurodevelopment were grouped into effect biomarkers (serum brain-derived neurotrophic factor (BDNF) and serum/saliva cortisol), susceptibility markers (epigenetic markers and gene sequence variants) and other biomarkers (serum high-density lipoprotein (HDL), maternal iron (Fe) and calcium (Ca) status). Serum BDNF and plasma HDL are potential candidates to be further validated as effect markers for routine use in HBM studies of Pb, complemented by markers of Fe and Ca status to also address nutritional interactions related to neurodevelopmental disorders. For several markers, a causal relationship with Pb-induced neurodevelopmental toxicity is likely. Results on BDNF are discussed in relation to Adverse Outcome Pathway (AOP) 13 ("Chronic binding of antagonist to N-methyl-D-aspartate receptors (NMDARs) during brain development induces impairment of learning and memory abilities") of the AOP-Wiki. Further studies are needed to validate sensitive, reliable, and timely effect biomarkers, especially for low to moderate Pb exposure scenarios.
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17
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Pistollato F, Carpi D, Mendoza-de Gyves E, Paini A, Bopp SK, Worth A, Bal-Price A. Combining in vitro assays and mathematical modelling to study developmental neurotoxicity induced by chemical mixtures. Reprod Toxicol 2021; 105:101-119. [PMID: 34455033 PMCID: PMC8522961 DOI: 10.1016/j.reprotox.2021.08.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 07/30/2021] [Accepted: 08/24/2021] [Indexed: 12/12/2022]
Abstract
Prenatal and postnatal co-exposure to multiple chemicals at the same time may have deleterious effects on the developing nervous system. We previously showed that chemicals acting through similar mode of action (MoA) and grouped based on perturbation of brain derived neurotrophic factor (BDNF), induced greater neurotoxic effects on human induced pluripotent stem cell (hiPSC)-derived neurons and astrocytes compared to chemicals with dissimilar MoA. Here we assessed the effects of repeated dose (14 days) treatments with mixtures containing the six chemicals tested in our previous study (Bisphenol A, Chlorpyrifos, Lead(II) chloride, Methylmercury chloride, PCB138 and Valproic acid) along with 2,2'4,4'-tetrabromodiphenyl ether (BDE47), Ethanol, Vinclozolin and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)), on hiPSC-derived neural stem cells undergoing differentiation toward mixed neurons/astrocytes up to 21 days. Similar MoA chemicals in mixtures caused an increase of BDNF levels and neurite outgrowth, and a decrease of synapse formation, which led to inhibition of electrical activity. Perturbations of these endpoints are described as common key events in adverse outcome pathways (AOPs) specific for DNT. When compared with mixtures tested in our previous study, adding similarly acting chemicals (BDE47 and EtOH) to the mixture resulted in a stronger downregulation of synapses. A synergistic effect on some synaptogenesis-related features (PSD95 in particular) was hypothesized upon treatment with tested mixtures, as indicated by mathematical modelling. Our findings confirm that the use of human iPSC-derived mixed neuronal/glial models applied to a battery of in vitro assays anchored to key events in DNT AOP networks, combined with mathematical modelling, is a suitable testing strategy to assess in vitro DNT induced by chemical mixtures.
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Affiliation(s)
| | - Donatella Carpi
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | | | - Alicia Paini
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | | | - Andrew Worth
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Anna Bal-Price
- European Commission, Joint Research Centre (JRC), Ispra, Italy.
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18
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Wang R, Wu Z, Liu M, Wu Y, Li Q, Ba Y, Zhang H, Cheng X, Zhou G, Huang H. Resveratrol reverses hippocampal synaptic markers injury and SIRT1 inhibition against developmental Pb exposure. Brain Res 2021; 1767:147567. [PMID: 34175265 DOI: 10.1016/j.brainres.2021.147567] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 05/30/2021] [Accepted: 06/21/2021] [Indexed: 12/01/2022]
Abstract
Lead (Pb) exposure damages synaptic structural plasticity that results in cognitive impairment. Resveratrol, a natural polyphenolic compound, is one of the most potent agonists of silencing information regulator 1 (SIRT1) discovered to date. However, the effects of SIRT1 on synaptic functional plasticity in early life Pb exposure are not well studied. Herein, the purpose of this study is to investigate the expression of synaptic markers and SIRT1 in rats exposed to Pb and to evaluate the regulatory effect of resveratrol during this process. The Pb exposed male SD pups were treated with resveratrol (50 mg/kg/d) or EDTA (150 mg/kg/d) followed by hippocampal and blood sampling for analysis at postnatal day 21 (PND21). In the Morrris water maze test, resveratrol treatement protected the rats against Pb-induced impairment of learning and memory (P < 0.05). Resveratrol also enhanced the expression of brain-derived neurotrophic factor (BDNF, P < 0.001 vs 0.2% Pb group), and reversed the effects of Pb exposure on SIRT1(P < 0.001 vs 0.2% Pb group). The DG, CA1 and CA3 regions of the hippocampus showed a considerable increase in the expression of pre- and postsynaptic proteins (P < 0.001 vs 0.2% Pb group). In conclusion, our study demonstrated that resveratrol, through the activation of SIRT1, played a protective role against Pb-induced defects in synaptic plasticity, and suggested a new potential adjuvant treatment for Pb poisoning.
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Affiliation(s)
- Ruike Wang
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province, China; Environment and Health Innovation Team, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province 450001, China
| | - Zuntao Wu
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province, China; Environment and Health Innovation Team, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province 450001, China
| | - Mengchen Liu
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province, China; Environment and Health Innovation Team, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province 450001, China
| | - Yingying Wu
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province, China; Environment and Health Innovation Team, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province 450001, China
| | - Qiong Li
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province, China; Environment and Health Innovation Team, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province 450001, China
| | - Yue Ba
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province, China; Environment and Health Innovation Team, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province 450001, China
| | - Huizhen Zhang
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province, China; Environment and Health Innovation Team, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province 450001, China
| | - Xuemin Cheng
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province, China; Environment and Health Innovation Team, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province 450001, China
| | - Guoyu Zhou
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province, China; Environment and Health Innovation Team, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province 450001, China
| | - Hui Huang
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province, China; Environment and Health Innovation Team, College of Public Health, Zhengzhou University, Zhengzhou, Henan Province 450001, China.
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19
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Sachana M, Willett C, Pistollato F, Bal-Price A. The potential of mechanistic information organised within the AOP framework to increase regulatory uptake of the developmental neurotoxicity (DNT) in vitro battery of assays. Reprod Toxicol 2021; 103:159-170. [PMID: 34147625 PMCID: PMC8279093 DOI: 10.1016/j.reprotox.2021.06.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 05/19/2021] [Accepted: 06/04/2021] [Indexed: 12/24/2022]
Abstract
Current in vivo DNT testing for regulatory purposes is not effective. In vitro assays anchored to key neurodevelopmental processes are available. Development of Adverse Outcome Pathways is required to increase mechanistic understanding of DNT effects. DNT Integrated Approaches to Testing and Assessment for various regulatory purposes should be developed. The OECD Guidance Document on use of in vitro DNT battery of assays is currently under development.
A major challenge in regulatory developmental neurotoxicity (DNT) assessment is lack of toxicological information for many compounds. Therefore, the Test Guidelines programme of the Organisation for Economic Cooperation and Development (OECD) took the initiative to coordinate an international collaboration between diverse stakeholders to consider integration of alternative approaches towards improving the current chemical DNT testing. During the past few years, a series of workshops was organized during which a consensus was reached that incorporation of a DNT testing battery that relies on in vitro assays anchored to key neurodevelopmental processes should be developed. These key developmental processes include neural progenitor cell proliferation, neuronal and oligodendrocyte differentiation, neural cell migration, neurite outgrowth, synaptogenesis and neuronal network formation, as well key events identified in the existing Adverse Outcome Pathways (AOPs). AOPs deliver mechanistic information on the causal links between molecular initiating event, intermediate key events and an adverse outcome of regulatory concern, providing the biological context to facilitate development of Integrated Approaches to Testing and Assessment (IATA) for various regulatory purposes. Developing IATA case studies, using mechanistic information derived from AOPs, is expected to increase scientific confidence for the use of in vitro methods within an IATA, thereby facilitating regulatory uptake. This manuscript summarizes the current state of international efforts to enhance DNT testing by using an in vitro battery of assays focusing on the role of AOPs in informing the development of IATA for different regulatory purposes, aiming to deliver an OECD guidance document on use of in vitro DNT battery of assays that include in vitro data interpretation.
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Affiliation(s)
- Magdalini Sachana
- Environment Health and Safety Division, Environment Directorate, Organisation for Economic Co-Operation and Development (OECD), 75775, Paris Cedex 16, France
| | - Catherine Willett
- Humane Society International, 1255 23rd Street NW, Washington, DC, 20037, USA
| | | | - Anna Bal-Price
- European Commission Joint Research Centre (JRC), Ispra, Italy.
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20
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Davidsen N, Lauvås AJ, Myhre O, Ropstad E, Carpi D, Gyves EMD, Berntsen HF, Dirven H, Paulsen RE, Bal-Price A, Pistollato F. Exposure to human relevant mixtures of halogenated persistent organic pollutants (POPs) alters neurodevelopmental processes in human neural stem cells undergoing differentiation. Reprod Toxicol 2021; 100:17-34. [PMID: 33333158 PMCID: PMC7992035 DOI: 10.1016/j.reprotox.2020.12.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 12/03/2020] [Accepted: 12/11/2020] [Indexed: 12/11/2022]
Abstract
Halogenated persistent organic pollutants (POPs) like perfluorinated alkylated substances (PFASs), brominated flame retardants (BFRs), organochlorine pesticides and polychlorinated biphenyls (PCBs) are known to cause cancer, immunotoxicity, neurotoxicity and interfere with reproduction and development. Concerns have been raised about the impact of POPs upon brain development and possibly neurodevelopmental disorders. The developing brain is a particularly vulnerable organ due to dynamic and complex neurodevelopmental processes occurring early in life. However, very few studies have reported on the effects of POP mixtures at human relevant exposures, and their impact on key neurodevelopmental processes using human in vitro test systems. Aiming to reduce this knowledge gap, we exposed mixed neuronal/glial cultures differentiated from neural stem cells (NSCs) derived from human induced pluripotent stem cells (hiPSCs) to reconstructed mixtures of 29 different POPs using concentrations comparable to Scandinavian human blood levels. Effects of the POP mixtures on neuronal proliferation, differentiation and synaptogenesis were evaluated using in vitro assays anchored to common key events identified in the existing developmental neurotoxicity (DNT) adverse outcome pathways (AOPs). The present study showed that mixtures of POPs (in particular brominated and chlorinated compounds) at human relevant concentrations increased proliferation of NSCs and decreased synapse number. Based on a mathematical modelling, synaptogenesis and neurite outgrowth seem to be the most sensitive DNT in vitro endpoints. Our results indicate that prenatal exposure to POPs may affect human brain development, potentially contributing to recently observed learning and memory deficits in children.
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Affiliation(s)
- Nichlas Davidsen
- Department of Environmental Health, Section for Toxicology and Risk Assessment, Norwegian Institute of Public Health, Oslo, Norway
| | - Anna Jacobsen Lauvås
- Department of Environmental Health, Section for Toxicology and Risk Assessment, Norwegian Institute of Public Health, Oslo, Norway
| | - Oddvar Myhre
- Department of Environmental Health, Section for Toxicology and Risk Assessment, Norwegian Institute of Public Health, Oslo, Norway
| | - Erik Ropstad
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Donatella Carpi
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | | | - Hanne Friis Berntsen
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway; National Institute of Occupational Health, Oslo, Norway
| | - Hubert Dirven
- Department of Environmental Health, Section for Toxicology and Risk Assessment, Norwegian Institute of Public Health, Oslo, Norway
| | - Ragnhild E Paulsen
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, Norway
| | - Anna Bal-Price
- European Commission, Joint Research Centre (JRC), Ispra, Italy
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21
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Lewandowski Ł, Urbanowicz I, Kepinska M, Milnerowicz H. Concentration/activity of superoxide dismutase isozymes and the pro-/antioxidative status, in context of type 2 diabetes and selected single nucleotide polymorphisms (genes: INS, SOD1, SOD2, SOD3) - Preliminary findings. Biomed Pharmacother 2021; 137:111396. [PMID: 33761612 DOI: 10.1016/j.biopha.2021.111396] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 02/04/2021] [Accepted: 02/10/2021] [Indexed: 11/29/2022] Open
Abstract
The alterations in concentration/activity of superoxide dismutase isozymes in the context of type 2 diabetes or obesity are well-described. Moreover, many hereditary factors, including single-nucleotide polymorphisms (SNPs) of genes for coding insulin, insulin receptors, or insulin receptor substrates (INS, INSR, IRS1, IRS2) or superoxide dismutase isozymes (SOD1, SOD2, SOD3), have been linked with the incidence of obesity and diabetes. However, the underlying changes in the plasma concentration/activity of superoxide dismutase isozymes and their potential connection with the said hereditary factors remain unexplored. Previously, we have observed that the plasma concentration/activity of superoxide dismutase isozymes differs in the context of obesity and/or rs2234694 (SOD1) and rs4880 (SOD2) and that the concentrations of SOD1, SOD2, SOD3 are correlated with each other. Intersexual variability of SOD1 concentration was detected regardless of obesity. In this study, the variability of concentration/activity of superoxide dismutase isozymes in plasma is considered in the context of type 2 diabetes and/or SNPs: rs2234694 (SOD1), rs5746105 (SOD2), rs4880 (SOD2), rs927450 (SOD2), rs8192287 (SOD3). Genotypic variability of SNP rs3842729 (INS), previously studied in the context of insulin-dependent diabetes, is investigated in terms of selected clinical parameters associated with type 2 diabetes. This study revealed higher SOD1 concentration in diabetic men compared to women, and extremely high SOD1 concentration, higher total superoxide dismutase, and copper-zinc superoxide dismutase activity, and lower superoxide dismutase and copper-zinc superoxide dismutase activity (when adjusted for the concentration of SODs) in the diabetic group regardless of sex. Multiple logistic regression, applied to explore possible links between the studied SNPs and other factors with the odds of type 2 diabetes or obesity, revealed that the genotypic variability of rs4880 (SOD2) could affect these odds, supporting the findings of several other studies.
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Affiliation(s)
- Łukasz Lewandowski
- Department of Biomedical and Environmental Analyses, Faculty of Pharmacy, Wroclaw Medical University, Borowska Street 211, 50-556 Wrocław, Poland.
| | - Iwona Urbanowicz
- Department of Clinical Chemistry and Laboratory Hematology, Faculty of Pharmacy, Wroclaw Medical University, Borowska Street 211A, 50-556 Wrocław, Poland
| | - Marta Kepinska
- Department of Biomedical and Environmental Analyses, Faculty of Pharmacy, Wroclaw Medical University, Borowska Street 211, 50-556 Wrocław, Poland
| | - Halina Milnerowicz
- Department of Biomedical and Environmental Analyses, Faculty of Pharmacy, Wroclaw Medical University, Borowska Street 211, 50-556 Wrocław, Poland
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Abstract
Lead (Pb2+) is a non-essential metal with numerous industrial applications that have led to ts ubiquity in the environment. Thus, not only occupational-exposed individuals' health is compromised, but also that of the general population and in particular children. Notably, although the central nervous system is particularly susceptible to Pb2+, other systems are affected as well. The present study focuses on molecular mechanisms that underlie the effects that arise from the presence of Pb2+ in situ in the brain, and the possible toxic effects that follows. As the brain barriers represent the first target of systemic Pb2+, mechanisms of Pb2+ entry into the brain are discussed, followed by a detailed discussion on neurotoxic mechanisms, with special emphasis on theories of ion mimicry, mitochondrial dysfunction, redox imbalance, and neuroinflammation. Most importantly, the confluence and crosstalk between these events is combined into a cogent mechanism of toxicity, by intertwining recent and old evidences from humans, in vitro cell culture and experimental animals. Finally, pharmacological interventions, including chelators, antioxidants substances, anti-inflammatory drugs, or their combination are reviewed as integrated approaches to ameliorate Pb2+ harmful effects in both developing or adult organisms.
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Affiliation(s)
- Miriam B. Virgolini
- IFEC CONICET. IFEC-CONICET. Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba. Haya de la Torre y Medina Allende, Ciudad Universitaria, 5016, Córdoba, Argentina
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA and IM Sechenov First Moscow State Medical University (Sechenov University), 119146, Moscow, Russia
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Ijomone OM, Ijomone OK, Iroegbu JD, Ifenatuoha CW, Olung NF, Aschner M. Epigenetic influence of environmentally neurotoxic metals. Neurotoxicology 2020; 81:51-65. [PMID: 32882300 PMCID: PMC7708394 DOI: 10.1016/j.neuro.2020.08.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 08/25/2020] [Accepted: 08/25/2020] [Indexed: 02/08/2023]
Abstract
Continuous globalization and industrialization have ensured metals are an increasing aspect of daily life. Their usefulness in manufacturing has made them vital to national commerce, security and global economy. However, excess exposure to metals, particularly as a result of environmental contamination or occupational exposures, has been detrimental to overall health. Excess exposure to several metals is considered environmental risk in the aetiology of several neurological and neurodegenerative diseases. Metal-induced neurotoxicity has been a major health concern globally with intensive research to unravel the mechanisms associated with it. Recently, greater focus has been directed at epigenetics to better characterize the underlying mechanisms of metal-induced neurotoxicity. Epigenetic changes are those modifications on the DNA that can turn genes on or off without altering the DNA sequence. This review discusses how epigenetic changes such as DNA methylation, post translational histone modification and noncoding RNA-mediated gene silencing mediate the neurotoxic effects of several metals, focusing on manganese, arsenic, nickel, cadmium, lead, and mercury.
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Affiliation(s)
- Omamuyovwi M Ijomone
- The Neuro- Lab, Department of Human Anatomy, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria.
| | - Olayemi K Ijomone
- The Neuro- Lab, Department of Human Anatomy, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria; Department of Anatomy, University of Medical Sciences, Ondo, Nigeria
| | - Joy D Iroegbu
- The Neuro- Lab, Department of Human Anatomy, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria
| | - Chibuzor W Ifenatuoha
- The Neuro- Lab, Department of Human Anatomy, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria
| | - Nzube F Olung
- The Neuro- Lab, Department of Human Anatomy, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria
| | - Michael Aschner
- Departments of Molecular Pharmacology and Neurosciences, Albert Einstein College of Medicine, NY, USA.
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Gu X, Huang X, Li D, Bi N, Yu X, Wang HL. Nuclear accumulation of histone deacetylase 4 (HDAC4) by PP1-mediated dephosphorylation exerts neurotoxicity in Pb-exposed neural cells. Neurotoxicology 2020; 81:395-405. [PMID: 33080273 DOI: 10.1016/j.neuro.2020.10.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 10/13/2020] [Accepted: 10/13/2020] [Indexed: 10/23/2022]
Abstract
Lead (Pb) is an environmental contaminant that primarily affects the central nervous system, particularly the developing brain. Recently, increasing evidence indicates the important roles of histone deacetylases (HDACs) in Pb-induced neurotoxicity. However, the precise molecular mechanisms involving HDAC4 remains unknown. The purpose of this study was to investigate the role of HDAC4 in Pb-induced neurotoxicity both in vivo and in vitro. In vitro study, PC12 cells were exposed to Pb (10 μM) for 24 h, then the mRNA and protein levels of HDAC4 were analyzed. In vivo study, pregnant rats and their female offspring were treated with lead (50 ppm) until postnatal day 30. Then the pups were sacrificed and the mRNA and protein levels of HDAC4 in the hippocampus were analyzed. The results showed that HDAC4 was significantly increased in both PC12 cells and rat hippocampus upon Pb exposure. Blockade of HDAC4 with either LMK-235 (an inhibitor of HDAC4) or shHDAC4 (HDAC4-knocking down plasmid) ameliorated the Pb-induced neurite outgrowth deficits. Interestingly, HDAC4 was aberrantly accumulated in the nucleus upon Pb exposure. By contrast, blocking the HDAC4 shuffling from the cytosol to the nucleus with ΔNLS2-HDAC4 (the cytosol-localized HDAC4 mutant) was able to rescue the neuronal impairment. In addition, Pb increased PP1 (protein phosphatase 1) expression which in turn influenced the subcellular localization of HDAC4 by dephosphorylation of specific serine/threonine residues. What's more, blockade of PP1 with PP1-knocking down construct (shPP1) ameliorated Pb-induced neurite outgrowth deficits. Taken together, nuclear accumulation of HDAC4 by PP1-mediated dephosphorylation involved in Pb-induced neurotoxicity. This study might provide a promising molecular target for medical intervention with environmental cues.
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Affiliation(s)
- Xiaozhen Gu
- School of Food and Biological Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, 230009, Hefei, China
| | - Xiyao Huang
- School of Food and Biological Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, 230009, Hefei, China
| | - Danyang Li
- School of Food and Biological Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, 230009, Hefei, China
| | - Nanxi Bi
- School of Food and Biological Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, 230009, Hefei, China
| | - Xi Yu
- School of Food and Biological Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, 230009, Hefei, China
| | - Hui-Li Wang
- School of Food and Biological Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, 230009, Hefei, China.
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25
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Loth MK, Guariglia SR, Re DB, Perez J, de Paiva VN, Dziedzic JL, Chambers JW, Azzam DJ, Guilarte TR. A Novel Interaction of Translocator Protein 18 kDa (TSPO) with NADPH Oxidase in Microglia. Mol Neurobiol 2020; 57:4467-4487. [PMID: 32743737 PMCID: PMC7515859 DOI: 10.1007/s12035-020-02042-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 07/24/2020] [Indexed: 12/12/2022]
Abstract
In the brain neuropil, translocator protein 18 kDa (TSPO) is a stress response protein that is upregulated in microglia and astrocytes in diverse central nervous system pathologies. TSPO is widely used as a biomarker of neuroinflammation in preclinical and clinical neuroimaging studies. However, there is a paucity of knowledge on the function(s) of TSPO in glial cells. In this study, we explored a putative interaction between TSPO and NADPH oxidase 2 (NOX2) in microglia. We found that TSPO associates with gp91phox and p22phox, the principal subunits of NOX2 in primary murine microglia. The association of TSPO with gp91phox and p22phox was observed using co-immunoprecipitation, confocal immunofluorescence imaging, and proximity ligation assay. We found that besides gp91phox and p22phox, voltage-dependent anion channel (VDAC) also co-immunoprecipitated with TSPO consistent with previous reports. When we compared lipopolysaccharide (LPS) stimulated microglia to vehicle control, we found that a lower amount of gp91phox and p22phox protein co-immunoprecipitated with TSPO suggesting a disruption of the TSPO-NOX2 subunits association. TSPO immuno-gold electron microscopy confirmed that TSPO is present in the outer mitochondrial membrane but it is also found in the endoplasmic reticulum (ER), mitochondria-associated ER membrane (MAM), and in the plasma membrane. TSPO localization at the MAM may represent a subcellular site where TSPO interacts with gp91phox and p22phox since the MAM is a point of communication between outer mitochondria membrane proteins (TSPO) and ER proteins (gp91phox and p22phox) where they mature and form the cytochrome b558 (Cytb558) heterodimer. We also found that an acute burst of reactive oxygen species (ROS) increased TSPO levels on the surface of microglia and this effect was abrogated by a ROS scavenger. These results suggest that ROS production may alter the subcellular distribution of TSPO. Collectively, our findings suggest that in microglia, TSPO is associated with the major NOX2 subunits gp91phox and p22phox. We hypothesize that this interaction may regulate Cytb558 formation and modulate NOX2 levels, ROS production, and redox homeostasis in microglia.
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Affiliation(s)
- Meredith K Loth
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, USA
| | - Sara R Guariglia
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, USA
| | - Diane B Re
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, USA
| | - Juan Perez
- Department of Environmental Health Sciences, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL, 33199, USA
| | - Vanessa Nunes de Paiva
- Department of Environmental Health Sciences, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL, 33199, USA
| | - Jennifer L Dziedzic
- Department of Environmental Health Sciences, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL, 33199, USA
| | - Jeremy W Chambers
- Department of Environmental Health Sciences, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL, 33199, USA
| | - Diana J Azzam
- Department of Environmental Health Sciences, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL, 33199, USA
| | - Tomás R Guilarte
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, USA.
- Department of Environmental Health Sciences, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL, 33199, USA.
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26
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Zhou R, Zhao J, Li D, Chen Y, Xiao Y, Fan A, Chen XT, Wang HL. Combined exposure of lead and cadmium leads to the aggravated neurotoxicity through regulating the expression of histone deacetylase 2. CHEMOSPHERE 2020; 252:126589. [PMID: 32234630 DOI: 10.1016/j.chemosphere.2020.126589] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Revised: 03/10/2020] [Accepted: 03/21/2020] [Indexed: 06/11/2023]
Abstract
Lead (Pb) and cadmium (Cd) are common heavy metals in the environment, exerting detrimental effects on central nervous system. Although increasing evidence demonstrated the Pb and Cd-induced neurotoxicity, the exact epigenetic mechanisms induced by combined exposure (co-exposure) of Pb and Cd are still unclear. In this study, the neurotoxicity of individual exposure and co-exposure to Pb and Cd in vivo (150 ppm and 5 ppm respectively) and in vitro (10 μM and 0.1 μM respectively) was investigated. The results showed that neurite outgrowth was inhibited by either individual or combined exposure to Pb/Cd, whereas the co-exposure aggravated the inhibitory effect in PC12 cells. The results of Morris Water Maze (MWM), Y maze and Golgi-Cox staining showed that either Pb or Cd alone exposure damaged the ability of learning and memory and decreased the dendritic spine density in both the hippocampal CA1 and DG area of Sprague---Dawley (SD) rats, and that the co-exposure aggravated the damages. Subsequently, histone deacetylase (HDAC) 2 was significantly increased in both hippocampal tissues and PC12 cells co-exposed to Pb and Cd, and the treatment of trichostatin A (TSA) and HDAC2-knocking down construct (shHDAC2) could markedly prevent neurite outgrowth impairment in PC12 cells. In summary, HDAC2 plays essential regulatory roles in neurotoxicity induced by the co-exposure to Pb and Cd, providing a potential molecular target for neurological intervention.
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Affiliation(s)
- Ruiqing Zhou
- School of Food and Biological Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui, 230009, PR China
| | - Jing Zhao
- School of Food and Biological Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui, 230009, PR China
| | - Danyang Li
- School of Food and Biological Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui, 230009, PR China
| | - Yao Chen
- School of Pharmacy, Anhui Medical University, Hefei, Anhui, 230031, PR China
| | - Yanyan Xiao
- School of Pharmacy, Anhui Medical University, Hefei, Anhui, 230031, PR China
| | - Anni Fan
- School of Food and Biological Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui, 230009, PR China
| | - Xiang-Tao Chen
- School of Pharmacy, Anhui Medical University, Hefei, Anhui, 230031, PR China.
| | - Hui-Li Wang
- School of Food and Biological Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui, 230009, PR China.
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27
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Meyer DN, Crofts EJ, Akemann C, Gurdziel K, Farr R, Baker BB, Weber D, Baker TR. Developmental exposure to Pb 2+ induces transgenerational changes to zebrafish brain transcriptome. CHEMOSPHERE 2020; 244:125527. [PMID: 31816550 PMCID: PMC7015790 DOI: 10.1016/j.chemosphere.2019.125527] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/27/2019] [Accepted: 11/30/2019] [Indexed: 05/24/2023]
Abstract
Lead (Pb2+) is a major public health hazard for urban children, with profound and well-characterized developmental and behavioral implications across the lifespan. The ability of early Pb2+ exposure to induce epigenetic changes is well-established, suggesting that Pb2+-induced neurobehavioral deficits may be heritable across generations. Understanding the long-term and multigenerational repercussions of lead exposure is crucial for clarifying both the genotypic alterations behind these behavioral outcomes and the potential mechanism of heritability. To study this, zebrafish (Danio rerio) embryos (<2 h post fertilization; EK strain) were exposed for 24 h to waterborne Pb2+ at a concentration of 10 μM. This exposed F0 generation was raised to adulthood and spawned to produce the F1 generation, which was subsequently spawned to produce the F2 generation. Previous avoidance conditioning studies determined that a 10 μM Pb2+ dose resulted in learning impairments persisting through the F2 generation. RNA was extracted from control- and 10 μM Pb2+-lineage F2 brains, (n = 10 for each group), sequenced, and transcript expression was quantified utilizing Quant-Seq. 648 genes were differentially expressed in the brains of F2 lead-lineage fish versus F2 control-lineage fish. Pathway analysis revealed altered genes in processes including synaptic function and plasticity, neurogenesis, endocrine homeostasis, and epigenetic modification, all of which are implicated in lead-induced neurobehavioral deficits and/or their inheritance. These data will inform future investigations to elucidate the mechanism of adult-onset and transgenerational health effects of developmental lead exposure.
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Affiliation(s)
- Danielle N Meyer
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, MI, USA; Institute of Environmental Health Sciences, School of Medicine, Wayne State University, Detroit, MI, USA
| | - Emily J Crofts
- Institute of Environmental Health Sciences, School of Medicine, Wayne State University, Detroit, MI, USA
| | - Camille Akemann
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, MI, USA; Institute of Environmental Health Sciences, School of Medicine, Wayne State University, Detroit, MI, USA
| | - Katherine Gurdziel
- Applied Genome Technology Center, School of Medicine, Wayne State University, Detroit, MI, USA
| | - Rebecca Farr
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, MI, USA
| | - Bridget B Baker
- Institute of Environmental Health Sciences, School of Medicine, Wayne State University, Detroit, MI, USA; Division of Laboratory Animal Resources, School of Medicine, Wayne State University, Detroit, MI, USA
| | - Daniel Weber
- Children's Environmental Health Sciences Core Center, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Tracie R Baker
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, MI, USA; Institute of Environmental Health Sciences, School of Medicine, Wayne State University, Detroit, MI, USA.
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28
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Owsianowska J, Kamińska MS, Bosiacki M, Chlubek D, Karakiewicz B, Jurczak A, Stanisławska M, Barczak K, Grochans E. Depression, changes in peripheral blood cell count, and changes in selected biochemical parameters related to lead concentration in whole blood (Pb-B) of women in the menopausal period. J Trace Elem Med Biol 2020; 61:126501. [PMID: 32289550 DOI: 10.1016/j.jtemb.2020.126501] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Revised: 01/24/2020] [Accepted: 03/18/2020] [Indexed: 11/24/2022]
Abstract
THE AIM The aim of this study was to assess the severity of depression, vasomotor symptoms, changes in peripheral blood cell count, and selected biochemical parameters in relation to the concentration of lead in whole blood of women in the perimenopausal period. METHODS The study sample consisted of 233 women from the general population of the West Pomeranian Province (Poland) in age between 44-65 years. The intensity of menopausal symptoms was examined using the Blatt-Kupperman Index, and the severity of depression using the Beck Depression Inventory. The following biochemical data were evaluated: concentrations of glucose, triglycerides, HDL, C-reactive protein, glycated haemoglobin, cortisol, insulin, blood cell count, and lead concentration in whole blood (Pb-B). RESULTS A whole blood Pb concentration below 5 μg/dl was found in 55 subjects (23.61 %), in 142 women (60.94 %) it ranged from 5 to 10 μg/dl, while in 36 women (15.45 %) was higher than 10 μg/dl. There was a strong positive correlation between Pb concentration in the blood of the examined women and the severity of depressive symptoms (Rs=+0.60, p = 0.001). The lowest mean values for total leukocytes (5.07 ± 1.22 thousand/μl) and neutrophils (2.76 ± 0.86 thousand/μl) were found in women with Pb concentration above 10 μg/dl (p < 0.05). There was a significant negative correlation between the number of total leukocytes (r=-0.45, p = 0.002) and neutrophils (r=-0.50, p = 0.001) and blood Pb concentration. Analysis showed statistically significant differences in glucose concentration (p < 0.05) between groups. Blood glucose was higher in women with Pb-B <5 and between 5-10 μg/dl than in women with Pb-B >10 μg/dl. CONCLUSION Exposure to Pb may be a factor playing a significant role in the development of depressive symptoms in menopausal women. It may also be associated with glucose metabolism disorders and immunosuppression in women during this period of life.
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Affiliation(s)
- Joanna Owsianowska
- Department of Specialized Nursing, Faculty of Health Sciences, Pomeranian Medical University in Szczecin, 48 Żołnierska St., 71-210, Szczecin, Poland.
| | - Magdalena Sylwia Kamińska
- Subdepartment of Long-Term Care, Department of Social Medicine, Faculty of Health Sciences, Pomeranian Medical University in Szczecin, 48 Żołnierska St., 71-210, Szczecin, Poland.
| | - Mateusz Bosiacki
- Department of Functional Diagnostics and Physical Medicine, Faculty of Health Sciences, Pomeranian Medical University in Szczecin, 56 Żołnierska St., 71-210, Szczecin, Poland.
| | - Dariusz Chlubek
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, 72 Powstańców Wielkopolskich St., 70-111, Szczecin, Poland.
| | - Beata Karakiewicz
- Subdepartment of Social Medicine and Public Health, Department of Social Medicine, Faculty of Health Sciences, Pomeranian Medical University in Szczecin, 48 Żołnierska St., 71-210, Szczecin, Poland.
| | - Anna Jurczak
- Department of Specialized Nursing, Faculty of Health Sciences, Pomeranian Medical University in Szczecin, 48 Żołnierska St., 71-210, Szczecin, Poland.
| | - Marzanna Stanisławska
- Department of Nursing, Faculty of Health Sciences, Pomeranian Medical University in Szczecin, 48 Żołnierska St., 71-210, Szczecin, Poland.
| | - Katarzyna Barczak
- Department of Conservative Dentistry and Endodontics, Pomeranian Medical University, 72 Powstańców Wielkopolskich St., 70-111, Szczecin, Poland.
| | - Elżbieta Grochans
- Department of Nursing, Faculty of Health Sciences, Pomeranian Medical University in Szczecin, 48 Żołnierska St., 71-210, Szczecin, Poland.
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29
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Pistollato F, de Gyves EM, Carpi D, Bopp SK, Nunes C, Worth A, Bal-Price A. Assessment of developmental neurotoxicity induced by chemical mixtures using an adverse outcome pathway concept. Environ Health 2020; 19:23. [PMID: 32093744 PMCID: PMC7038628 DOI: 10.1186/s12940-020-00578-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 02/11/2020] [Indexed: 05/25/2023]
Abstract
BACKGROUND In light of the vulnerability of the developing brain, mixture risk assessment (MRA) for the evaluation of developmental neurotoxicity (DNT) should be implemented, since infants and children are co-exposed to more than one chemical at a time. One possible approach to tackle MRA could be to cluster DNT chemicals in a mixture on the basis of their mode of action (MoA) into 'similar' and 'dissimilar', but still contributing to the same adverse outcome, and anchor DNT assays to common key events (CKEs) identified in DNT-specific adverse outcome pathways (AOPs). Moreover, the use of human in vitro models, such as induced pluripotent stem cell (hiPSC)-derived neuronal and glial cultures would enable mechanistic understanding of chemically-induced adverse effects, avoiding species extrapolation. METHODS HiPSC-derived neural progenitors differentiated into mixed cultures of neurons and astrocytes were used to assess the effects of acute (3 days) and repeated dose (14 days) treatments with single chemicals and in mixtures belonging to different classes (i.e., lead(II) chloride and methylmercury chloride (heavy metals), chlorpyrifos (pesticide), bisphenol A (organic compound and endocrine disrupter), valproic acid (drug), and PCB138 (persistent organic pollutant and endocrine disrupter), which are associated with cognitive deficits, including learning and memory impairment in children. Selected chemicals were grouped based on their mode of action (MoA) into 'similar' and 'dissimilar' MoA compounds and their effects on synaptogenesis, neurite outgrowth, and brain derived neurotrophic factor (BDNF) protein levels, identified as CKEs in currently available AOPs relevant to DNT, were evaluated by immunocytochemistry and high content imaging analysis. RESULTS Chemicals working through similar MoA (i.e., alterations of BDNF levels), at non-cytotoxic (IC20/100), very low toxic (IC5), or moderately toxic (IC20) concentrations, induce DNT effects in mixtures, as shown by increased number of neurons, impairment of neurite outgrowth and synaptogenesis (the most sensitive endpoint as confirmed by mathematical modelling) and increase of BDNF levels, to a certain extent reproducing autism-like cellular changes observed in the brain of autistic children. CONCLUSIONS Our findings suggest that the use of human iPSC-derived mixed neuronal/glial cultures applied to a battery of assays anchored to key events of an AOP network represents a valuable approach to identify mixtures of chemicals with potential to cause learning and memory impairment in children.
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Affiliation(s)
| | | | - Donatella Carpi
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | | | - Carolina Nunes
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Andrew Worth
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Anna Bal-Price
- European Commission, Joint Research Centre (JRC), Ispra, Italy
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30
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Zhao J, Zhang Q, Zhang B, Xu T, Yin D, Gu W, Bai J. Developmental exposure to lead at environmentally relevant concentrations impaired neurobehavior and NMDAR-dependent BDNF signaling in zebrafish larvae. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 257:113627. [PMID: 31796321 DOI: 10.1016/j.envpol.2019.113627] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 11/12/2019] [Accepted: 11/13/2019] [Indexed: 06/10/2023]
Abstract
Lead (Pb) is one of the predominant heavy metals in e-waste recycling arears and recognized as a notorious environmental neurotoxic substance. However, whether Pb at environmentally relevant concentrations could cause neurobehavioral alteration and even what kind of signaling pathway Pb exposure would disrupt in zebrafish were not fully uncovered. In the present study, 6 h postfertilization (hpf) zebrafish embryos were exposed to Pb at the concentrations of 0, 5, 10, and 20 μg/L until 144 hpf. Then the neurobehavioral indicators including locomotor, turnings and social behaviors, and the expressions of selected genes concerning brain-derived neurotrophic factor (BDNF) signaling were investigated. The results showed that significant changes were obtained under 20 μg/L Pb exposure. The hypoactivity of zebrafish larvae in locomotor and turning behaviors was induced during the dark period, while hyperactivity was observed in a two-fish social assay during the light period. The significantly downregulation of genes encoding BDNF, its receptor TrkB, and N-methyl-D-aspartate glutamate receptor (NMDAR) suggested the involvement of NMDAR-dependent BDNF signaling pathway. Overall, our study demonstrated that developmental exposure to Pb at environmentally relevant concentrations caused obvious neurobehavioral impairment of zebrafish larvae by disrupting the NMDAR-dependent BDNF signaling, which could exert profound ecological consequences in the real environment.
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Affiliation(s)
- Jing Zhao
- WEEE Research Centre of Shanghai Polytechnic University, Shanghai Collaborative Innovation Centre for WEEE Recycling, Shanghai, 201209, China; Research Center of Resource Recycling Science and Engineering, Shanghai Polytechnic University, Shanghai, 201209, China
| | - Qing Zhang
- WEEE Research Centre of Shanghai Polytechnic University, Shanghai Collaborative Innovation Centre for WEEE Recycling, Shanghai, 201209, China; Research Center of Resource Recycling Science and Engineering, Shanghai Polytechnic University, Shanghai, 201209, China
| | - Bin Zhang
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Ting Xu
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.
| | - Daqiang Yin
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Weihua Gu
- WEEE Research Centre of Shanghai Polytechnic University, Shanghai Collaborative Innovation Centre for WEEE Recycling, Shanghai, 201209, China; Research Center of Resource Recycling Science and Engineering, Shanghai Polytechnic University, Shanghai, 201209, China
| | - Jianfeng Bai
- WEEE Research Centre of Shanghai Polytechnic University, Shanghai Collaborative Innovation Centre for WEEE Recycling, Shanghai, 201209, China; Research Center of Resource Recycling Science and Engineering, Shanghai Polytechnic University, Shanghai, 201209, China
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31
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Zou RX, Gu X, Ding JJ, Wang T, Bi N, Niu K, Ge M, Chen XT, Wang HL. Pb exposure induces an imbalance of excitatory and inhibitory synaptic transmission in cultured rat hippocampal neurons. Toxicol In Vitro 2019; 63:104742. [PMID: 31785328 DOI: 10.1016/j.tiv.2019.104742] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 11/12/2019] [Accepted: 11/24/2019] [Indexed: 12/16/2022]
Abstract
An appropriate balance of excitatory and inhibitory synapse maintains the network stability of the central nervous system. Our recent work showed lead (Pb) exposure can inhibit synaptic transmission in cultured hippocampal neurons. However, it is not clear whether Pb exposure disrupt the balance of excitatory and inhibitory synaptic transmission. Here, primary cultured hippocampal neurons from Sprague-Dawley (SD) rats were exposed to Pb (0.2 μM, 1 μM, 5 μM, respectively) from Days in Vitro (DIV) 7 to DIV 12 for 5 days and the excitatory and inhibitory synaptic transmission was examined. Patch clamp recording results showed that distinct from exposures of 0.2 μM and 5 μM, 1 μM Pb exposure significantly increased the mIPSC frequency and decreased the mEPSC frequency, leading to a uniform inhibitory outcome. Further, the number of inhibitory presynaptic puncta was significantly increased after 1 μM Pb exposure, while the number of excitatory presynaptic terminals was decreased. In addition 1 μM Pb increased the glutamic acid decarboxylase (GAD65) expression and the surface GABAA receptor (GABAAR) clusters. This shift might potentiate the synthesis of GABA and enhance the surface distribution of postsynaptic GABAAR clusters in hippocampus neurons. Together, these data showed that Pb exposure disrupted the balance of excitatory and inhibitory synaptic transmission via abnormal GABAergic neurotransmission.
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Affiliation(s)
- Rong-Xin Zou
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui 230009, PR China; School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Xiaozhen Gu
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Jin-Jun Ding
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Tiandong Wang
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Nanxi Bi
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Kang Niu
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Mengmeng Ge
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Xiang-Tao Chen
- School of Pharmacy, Anhui Medical University, Hefei, Anhui 230031, PR China.
| | - Hui-Li Wang
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui 230009, PR China; School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China.
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Casillas-Espinosa PM, Shultz SR, Braine EL, Jones NC, Snutch TP, Powell KL, O’Brien TJ. Disease-modifying effects of a novel T-type calcium channel antagonist, Z944, in a model of temporal lobe epilepsy. Prog Neurobiol 2019; 182:101677. [DOI: 10.1016/j.pneurobio.2019.101677] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 07/17/2019] [Accepted: 07/31/2019] [Indexed: 02/08/2023]
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Reis CF, de Souza ID, Morais DAA, Oliveira RAC, Imparato DO, de Almeida RMC, Dalmolin RJS. Systems Biology-Based Analysis Indicates Global Transcriptional Impairment in Lead-Treated Human Neural Progenitor Cells. Front Genet 2019; 10:791. [PMID: 31552095 PMCID: PMC6748217 DOI: 10.3389/fgene.2019.00791] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 07/26/2019] [Indexed: 01/19/2023] Open
Abstract
Lead poisoning effects are wide and include nervous system impairment, peculiarly during development, leading to neural damage. Lead interaction with calcium and zinc-containing metalloproteins broadly affects cellular metabolism since these proteins are related to intracellular ion balance, activation of signaling transduction cascades, and gene expression regulation. In spite of lead being recognized as a neurotoxin, there are gaps in knowledge about the global effect of lead in modulating the transcription of entire cellular systems in neural cells. In order to investigate the effects of lead poisoning in a systemic perspective, we applied the transcriptogram methodology in an RNA-seq dataset of human embryonic-derived neural progenitor cells (ES-NP cells) treated with 30 µM lead acetate for 26 days. We observed early downregulation of several cellular systems involved with cell differentiation, such as cytoskeleton organization, RNA, and protein biosynthesis. The downregulated cellular systems presented big and tightly connected networks. For long treatment times (12 to 26 days), it was possible to observe a massive impairment in cell transcription profile. Taking the enriched terms together, we observed interference in all layers of gene expression regulation, from chromatin remodeling to vesicle transport. Considering that ES-NP cells are progenitor cells that can originate other neural cell types, our results suggest that lead-induced gene expression disturbance might impair cells’ ability to differentiate, therefore influencing ES-NP cells’ fate.
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Affiliation(s)
- Clovis F Reis
- Bioinformatics Multidisciplinary Environment - IMD, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Iara D de Souza
- Bioinformatics Multidisciplinary Environment - IMD, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Diego A A Morais
- Bioinformatics Multidisciplinary Environment - IMD, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Raffael A C Oliveira
- Bioinformatics Multidisciplinary Environment - IMD, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Danilo O Imparato
- Bioinformatics Multidisciplinary Environment - IMD, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Rita M C de Almeida
- Institute of Physics and National Institute of Science and Technology: Complex Systems, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Rodrigo J S Dalmolin
- Bioinformatics Multidisciplinary Environment - IMD, Federal University of Rio Grande do Norte, Natal, Brazil.,Department of Biochemistry - CB, Federal University of Rio Grande do Norte, Natal, Brazil
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Gu X, Xu Y, Xue WZ, Wu Y, Ye Z, Xiao G, Wang HL. Interplay of miR-137 and EZH2 contributes to the genome-wide redistribution of H3K27me3 underlying the Pb-induced memory impairment. Cell Death Dis 2019; 10:671. [PMID: 31511494 PMCID: PMC6739382 DOI: 10.1038/s41419-019-1912-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2019] [Revised: 08/13/2019] [Accepted: 08/26/2019] [Indexed: 01/20/2023]
Abstract
Compromised learning and memory is a common feature of multiple neurodegenerative disorders. A paradigm spatial memory impairment could be caused by developmental lead (Pb) exposure. Growing evidence implicates epigenetic modifications in the Pb-mediated memory deficits; however, how histone modifications exemplified by H3K27me3 (H3 Lys27 trimethylation) contribute to this pathogenesis remains poorly understood. Here we found that Pb exposure diminished H3K27me3 levels in vivo by suppressing EZH2 (enhancer of zeste homolog 2) expression at an early stage. EZH2 overexpression in Pb-treated rats rescued the H3K27me3 abundance and partially restored the normal spatial memory, as manifested by the rat performance in a Morris water maze test, and structural analysis of hippocampal spine densities. Furthermore, miR-137 and EZH2 constitute mutually inhibitory loop to regulate the H3K27me3 level, and this feedback regulation could be specifically activated by Pb treatment. Considering genes targeted by H3K27me3, ChIP-chip (chromatin immunoprecipitation on chip) studies revealed that Pb could remodel the genome-wide distribution of H3K27me3, represented by pathways like transcriptional regulation, developmental regulation, cell motion, and apoptosis, as well as a novel Wnt9b locus. As a Wnt isoform associated with canonical and noncanonical signaling, Wnt9b was regulated by the opposite modifications of H3K4me3 (H3 Lys4 trimethylation) and H3K27me3 in Pb-exposed neurons. Rescue trials further validated the contribution of Wnt9b to Pb-induced neuronal impairments, wherein canonical or noncanonical Wnt signaling potentially exhibited destructive or protective roles, respectively. In summary, the study reveals an epigenetic-based molecular change underlying Pb-triggered spatial memory deficits, and provides new potential avenues for our understanding of neurodegenerative diseases with environmental etiology.
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Affiliation(s)
- Xiaozhen Gu
- School of Food and Bioengineering, Hefei University of Technology, Hefei, Anhui, 230009, People's Republic of China
| | - Yi Xu
- School of Food and Bioengineering, Hefei University of Technology, Hefei, Anhui, 230009, People's Republic of China
| | - Wei-Zhen Xue
- School of Food and Bioengineering, Hefei University of Technology, Hefei, Anhui, 230009, People's Republic of China
| | - Yulan Wu
- School of Food and Bioengineering, Hefei University of Technology, Hefei, Anhui, 230009, People's Republic of China
| | - Zi Ye
- College of Life Science and Bio-engineering, Beijing University of Technology, Beijing, 100022, People's Republic of China
| | - Guiran Xiao
- School of Food and Bioengineering, Hefei University of Technology, Hefei, Anhui, 230009, People's Republic of China.
| | - Hui-Li Wang
- School of Food and Bioengineering, Hefei University of Technology, Hefei, Anhui, 230009, People's Republic of China.
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35
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Wu Y, Xu Y, Huang X, Ye D, Han M, Wang HL. Regulatory Roles of Histone Deacetylases 1 and 2 in Pb-induced Neurotoxicity. Toxicol Sci 2019; 162:688-701. [PMID: 29301062 DOI: 10.1093/toxsci/kfx294] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Lead (Pb) prevails among the environmental hazards against human health. Although increasing evidence highlights the epigenetic roles underlying the Pb-induced neurotoxicity, the exact mechanisms concerning histone acetylation and its causative agents are still at its infancy. In the present study, the roles of histone deacetylases 1 and 2 (HDAC1/2), as well as acetylation of Lys9 on histone H3 (Ac-H3K9), in Pb-induced neurotoxicity were investigated. Pb was administered to PC12 cells at 10 μM for 24 h. And Sprague Dawley rats were chronically exposed to Pb through drinking water containing 250 ppm Pb for 2 months. Owing to Pb exposure, it indicated that HDAC2 was up-regulated accompanied by Ac-H3K9 down-regulation. Meanwhile, chromatin immunoprecipitation assay revealed that the changes in HDAC2 were attributed to histone H3 Lys27 trimethylation occupancy on its promoter. Blockade of HDAC2 with either Trichostatin A or HDAC2-knocking down construct (shHDAC2) resulted in amelioration of neurite outgrowth deficits via increasing Ac-H3K9 levels. It implied that HDAC2 plays essential regulatory roles in Pb-induced neurotoxicity. And, coimmunoprecipitation trials revealed that HDAC2 colocalized with HDAC1, forming a so-called HDAC1/2 complex. Subsequently, it was shown that HDAC1/2 repression could markedly prevent neurite outgrowth impairment and rescue the spatial memory deficits caused by Pb exposure, unequivocally implicating this complex in the studied toxicological process. Furthermore, Notch2 maybe the functional target of the HDAC1/2 and Ac-H3K9 alterations. Our study provided insight into the precise roles of HDAC1/2 in Pb-induced neurotoxicity, and thereby provided a promising molecular target for medical intervention of neurological disorders with environmental etiology.
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Affiliation(s)
- Yulan Wu
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui Province 230009, PR China
| | - Yi Xu
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui Province 230009, PR China
| | - Xiyao Huang
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui Province 230009, PR China
| | - Danlei Ye
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui Province 230009, PR China
| | - Miaomiao Han
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui Province 230009, PR China
| | - Hui-Li Wang
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui Province 230009, PR China
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Zhou CC, Gao ZY, He YQ, Wu MQ, Chen F, Wang J, Liu JX, Yan CH. Effects of lead, mercury, aluminium and manganese co-exposure on the serum BDNF concentration of pre-school children in Taizhou, China. CHEMOSPHERE 2019; 217:158-165. [PMID: 30415114 DOI: 10.1016/j.chemosphere.2018.11.028] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 10/18/2018] [Accepted: 11/02/2018] [Indexed: 06/09/2023]
Abstract
Previous studies have shown that toxic metal exposure can have adverse effects on the nervous system of children, but the toxicology of metal co-exposure on neurodevelopment remains to be clarified. Brain derived neurotrophic factor (BDNF) plays an important role in nervous system development, but the possible effects of metal co-exposure on the serum BDNF concentrations of children remain unknown. A total of 561 children living in Taizhou City, China were recruited to participate in our cross-sectional multicenter survey. We measured their blood Pb, Hg, Al and Mn levels and serum BDNF concentrations as well as determined their associations in the total and within sex subgroups. The geometric means of the blood Pb, Hg, Al and Mn levels in all the participants were 67.18 μg/L, 1.01 μg/L, 52.03 μg/L and 18.26 μg/L, respectively. The serum BDNF concentration in children was 19.45 ng/mL. After adjusting for confounders, the blood Pb levels were significantly negatively associated with the serum BDNF concentrations in all the subjects and boys but not in girls. In addition, a significantly negative interaction between blood Pb and blood Hg and a positive interaction between blood Pb and blood Al on serum BDNF concentrations were also observed in boys but not in girls. Our findings highlight the toxic effects of metal co-exposure on serum BDNF levels in pre-school children and indicate that these effects might differ by gender, which suggest that special attention should be paid to the sex-specific effects of metal exposure.
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Affiliation(s)
- Can-Can Zhou
- MOE-Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, PR China
| | - Zhen-Yan Gao
- MOE-Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, PR China; Shanghai First Maternity and Infant Hospital, Tongji University, Shanghai, 200040, PR China
| | - Yu-Qiong He
- Department of Pharmacognosy, Second Military Medical University School of Pharmacy, Shanghai, 200433, PR China
| | - Mei-Qin Wu
- MOE-Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, PR China
| | - Fei Chen
- East China University of Science and Technology, Shanghai, 200237, PR China
| | - Ju Wang
- MOE-Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, PR China
| | - Jun-Xia Liu
- MOE-Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, PR China
| | - Chong-Huai Yan
- MOE-Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, PR China.
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Li D, Wang HL, Huang X, Gu X, Xue W, Xu Y. Identification and Functional Characterization of a New Splicing Variant of EZH2 in the Central Nervous System. Int J Biol Sci 2019; 15:69-80. [PMID: 30662348 PMCID: PMC6329929 DOI: 10.7150/ijbs.28129] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 09/26/2018] [Indexed: 12/29/2022] Open
Abstract
EZH2 plays vital roles in epigenetic regulation, neuronal development and cancer progression. Here a novel EZH2 variant, namely EZH2-X9 (X9 for short) resulting from alternative splicing, was isolated, identified and functionally characterized. X9 was highly expressed in the brains of SD rats, indicating a potentially distinguished role in the central nervous system (CNS). Owing to a transcript profiling, X9 was enriched in multiple brain regions at very early stage of life. Immunostaining validated the presence of the protein form of X9, which was localized similarly with the wild-type form, EZH2-WT. To investigate the functional consequence of X9, genetic intervention was performed in PC-12 cell line, a classic cellular model for neuronal development. It revealed that the depletion of either variant was sufficient to impair neuronal proliferation and differentiation significantly, an evidence that roles of X9 could not be complemented by EZH2-WT. Considering epigenetic regulation, X9 lost the capability to recruit the histone mark H3K27me3, but retained the cooperation with EED, as well as the repressive aspects in governing gene expression. Nonetheless, through profiling the genes affected, it's discovered that EZH2-WT and X9 markedly differed in their regulatory targets, as X9 intended to repress cell cycle- and autophagy-related genes, like GSK and MapILC3. Overall, a novel Ezh2 variant was characterized in the mammal CNS, providing insight with the structural and functional delineation of this key developmental switch, Ezh2.
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Affiliation(s)
- Danyang Li
- School of Food Science and Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, Hefei, Anhui Province, China
| | - Hui-Li Wang
- School of Food Science and Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, Hefei, Anhui Province, China
| | - Xiyao Huang
- School of Food Science and Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, Hefei, Anhui Province, China
| | - Xiaozhen Gu
- School of Food Science and Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, Hefei, Anhui Province, China
| | - Weizhen Xue
- School of Food Science and Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, Hefei, Anhui Province, China
| | - Yi Xu
- School of Food Science and Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, Hefei, Anhui Province, China
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Nam SM, Cho IS, Seo JS, Go TH, Kim JH, Nahm SS, Chang BJ, Lee JH. Ascorbic Acid Attenuates Lead-Induced Alterations in the Synapses in the Developing Rat Cerebellum. Biol Trace Elem Res 2019; 187:142-150. [PMID: 29696534 DOI: 10.1007/s12011-018-1354-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 04/17/2018] [Indexed: 11/26/2022]
Abstract
We evaluated the effect of lead (Pb) and ascorbic acid treatment of pregnant female rats on cerebellar development in pups. Pb was administered in drinking water (0.2% Pb acetate), and ascorbic acid (100 mg/kg) was administered through oral intubation. Fifteen female rats were randomly classified into control, Pb, and Pb plus ascorbic acid (PA) groups. The treatment of Pb and ascorbic acid treatments were terminated after birth to evaluate the effects on the gestational development of the cerebellum. At postnatal day 21 (PND21), pups were sacrificed, and blood Pb level was analyzed. Blood Pb levels of pups and dams were highest in the Pb group and reduced in the PA group. Immunohistochemistry and immunoblot assays were conducted to study the cerebellar expression levels of synaptic proteins. Along with a significant reduction in Purkinje cells, the reduction in presynaptic (synaptophysin) and postsynaptic (postsynaptic density protein 95, N-methyl-D-aspartate receptor subtype 1) marker proteins was observed in Pb-exposed pups. Ascorbic acid treatment significantly prevented Pb-induced impairment in the cerebellar synaptic proteins. Hypothesizing that brain-derived neurotrophic factor (BDNF) might be affected by Pb exposure given its importance in the regulation of synaptogenesis, we observed a Pb-induced decrease and ascorbic acid-mediated increase of BDNF in the cerebellum. Luxol fast blue staining and myelin basic protein analysis suggest that ascorbic acid treatment ameliorated the Pb exposure-induced reduction in the axonal fibers in the developing cerebellum. Overall, we conclude that ascorbic acid treatment during pregnancy can prevent Pb-induced impairments in the cerebellar development in rats.
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Affiliation(s)
- Sung Min Nam
- Department of Anatomy, College of Veterinary Medicine, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05030, Republic of Korea
- College of Veterinary Medicine and Veterinary Science Research Institute, Konkuk University, Seoul, 05030, Republic of Korea
| | - In-Sun Cho
- Department of Anatomy, College of Veterinary Medicine, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05030, Republic of Korea
- Korea Bio-Safety Institute Co. Ltd, Eumseong, Chungbuk, 27600, Republic of Korea
| | - Jin Seok Seo
- Department of Anatomy, College of Veterinary Medicine, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05030, Republic of Korea
| | - Tae-Hun Go
- Department of Anatomy, College of Veterinary Medicine, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05030, Republic of Korea
| | - Ji-Hye Kim
- Department of Rehabilitation Psychology, Seoul Rehabilitation Hospital, Seoul, 03428, Republic of Korea
| | - Sang-Soep Nahm
- Department of Anatomy, College of Veterinary Medicine, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05030, Republic of Korea
- College of Veterinary Medicine and Veterinary Science Research Institute, Konkuk University, Seoul, 05030, Republic of Korea
| | - Byung-Joon Chang
- Department of Anatomy, College of Veterinary Medicine, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05030, Republic of Korea.
- College of Veterinary Medicine and Veterinary Science Research Institute, Konkuk University, Seoul, 05030, Republic of Korea.
| | - Jong-Hwan Lee
- Department of Anatomy, College of Veterinary Medicine, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05030, Republic of Korea.
- College of Veterinary Medicine and Veterinary Science Research Institute, Konkuk University, Seoul, 05030, Republic of Korea.
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Rahman A, Rao MS, Khan KM. Intraventricular infusion of quinolinic acid impairs spatial learning and memory in young rats: a novel mechanism of lead-induced neurotoxicity. J Neuroinflammation 2018; 15:263. [PMID: 30217162 PMCID: PMC6137743 DOI: 10.1186/s12974-018-1306-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 09/04/2018] [Indexed: 12/20/2022] Open
Abstract
Background Lead (Pb), a heavy metal, and quinolinic acid (QA), a metabolite of the kynurenine pathway of tryptophan metabolism, are known neurotoxicants. Both Pb and QA impair spatial learning and memory. Pb activates astrocytes and microglia, which in turn induce the synthesis of QA. We hypothesized increased QA production in response to Pb exposure as a novel mechanism of Pb-neurotoxicity. Methods Two experimental paradigms were used. In experiment one, Wistar rat pups were exposed to Pb via their dams’ drinking water from postnatal day 1 to 21. Control group was given regular water. In the second protocol, QA (9 mM) or normal saline (as Vehicle Control) was infused into right lateral ventricle of 21-day old rats for 7 days using osmotic pumps. Learning and memory were assessed by Morris water maze test on postnatal day 30 or 45 in both Pb- and QA-exposed rats. QA levels in the Pb exposed rats were measured in blood by ELISA and in the brain by immunohistochemistry on postnatal days 45 and 60. Expression of various molecules involved in learning and memory was analyzed by Western blot. Means of control and experimental groups were compared with two-way repeated measure ANOVA (learning) and t test (all other variables). Results Pb exposure increased QA level in the blood (by ~ 58%) and increased (p < 0.05) the number of QA-immunoreactive cells in the cortex, and CA1, CA3 and dentate gyrus regions of the hippocampus, compared to control rats. In separate experiments, QA infusion impaired learning and short-term memory similar to Pb. PSD-95, PP1, and PP2A were decreased (p < 0.05) in the QA-infused rats, whereas tau phosphorylation was increased, compared to vehicle infused rats. Conclusion Putting together the results of the two experimental paradigms, we propose that increased QA production in response to Pb exposure is a novel mechanism of Pb-induced neurotoxicity.
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Affiliation(s)
- Abdur Rahman
- Department of Food Science and Nutrition, College of Life Sciences, Kuwait University, Kuwait City, Kuwait.
| | - Muddanna S Rao
- Department of Anatomy, Faculty of Medicine, Kuwait University, Kuwait City, Kuwait
| | - Khalid M Khan
- Department of Anatomy, Faculty of Medicine, Kuwait University, Kuwait City, Kuwait
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40
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Sachana M, Rolaki A, Bal-Price A. Development of the Adverse Outcome Pathway (AOP): Chronic binding of antagonist to N-methyl-d-aspartate receptors (NMDARs) during brain development induces impairment of learning and memory abilities of children. Toxicol Appl Pharmacol 2018; 354:153-175. [PMID: 29524501 PMCID: PMC6095943 DOI: 10.1016/j.taap.2018.02.024] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 02/26/2018] [Accepted: 02/28/2018] [Indexed: 01/06/2023]
Abstract
The Adverse Outcome Pathways (AOPs) are designed to provide mechanistic understanding of complex biological systems and pathways of toxicity that result in adverse outcomes (AOs) relevant to regulatory endpoints. AOP concept captures in a structured way the causal relationships resulting from initial chemical interaction with biological target(s) (molecular initiating event) to an AO manifested in individual organisms and/or populations through a sequential series of key events (KEs), which are cellular, anatomical and/or functional changes in biological processes. An AOP provides the mechanistic detail required to support chemical safety assessment, the development of alternative methods and the implementation of an integrated testing strategy. An example of the AOP relevant to developmental neurotoxicity (DNT) is described here following the requirements of information defined by the OECD Users' Handbook Supplement to the Guidance Document for developing and assessing AOPs. In this AOP, the binding of an antagonist to glutamate receptor N-methyl-d-aspartate (NMDAR) receptor is defined as MIE. This MIE triggers a cascade of cellular KEs including reduction of intracellular calcium levels, reduction of brain derived neurotrophic factor release, neuronal cell death, decreased glutamate presynaptic release and aberrant dendritic morphology. At organ level, the above mentioned KEs lead to decreased synaptogenesis and decreased neuronal network formation and function causing learning and memory deficit at organism level, which is defined as the AO. There are in vitro, in vivo and epidemiological data that support the described KEs and their causative relationships rendering this AOP relevant to DNT evaluation in the context of regulatory purposes.
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Affiliation(s)
| | | | - Anna Bal-Price
- European Commission, Joint Research Centre, Ispra, Italy.
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41
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Sachana M, Rolaki A, Bal-Price A. Development of the Adverse Outcome Pathway (AOP): Chronic binding of antagonist to N-methyl-d-aspartate receptors (NMDARs) during brain development induces impairment of learning and memory abilities of children. Toxicol Appl Pharmacol 2018; 354:153-175. [PMID: 29524501 DOI: 10.1787/5jlsqs5hcrmq-en] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 02/26/2018] [Accepted: 02/28/2018] [Indexed: 05/20/2023]
Abstract
The Adverse Outcome Pathways (AOPs) are designed to provide mechanistic understanding of complex biological systems and pathways of toxicity that result in adverse outcomes (AOs) relevant to regulatory endpoints. AOP concept captures in a structured way the causal relationships resulting from initial chemical interaction with biological target(s) (molecular initiating event) to an AO manifested in individual organisms and/or populations through a sequential series of key events (KEs), which are cellular, anatomical and/or functional changes in biological processes. An AOP provides the mechanistic detail required to support chemical safety assessment, the development of alternative methods and the implementation of an integrated testing strategy. An example of the AOP relevant to developmental neurotoxicity (DNT) is described here following the requirements of information defined by the OECD Users' Handbook Supplement to the Guidance Document for developing and assessing AOPs. In this AOP, the binding of an antagonist to glutamate receptor N-methyl-d-aspartate (NMDAR) receptor is defined as MIE. This MIE triggers a cascade of cellular KEs including reduction of intracellular calcium levels, reduction of brain derived neurotrophic factor release, neuronal cell death, decreased glutamate presynaptic release and aberrant dendritic morphology. At organ level, the above mentioned KEs lead to decreased synaptogenesis and decreased neuronal network formation and function causing learning and memory deficit at organism level, which is defined as the AO. There are in vitro, in vivo and epidemiological data that support the described KEs and their causative relationships rendering this AOP relevant to DNT evaluation in the context of regulatory purposes.
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Affiliation(s)
| | | | - Anna Bal-Price
- European Commission, Joint Research Centre, Ispra, Italy.
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Lu Z, Sun J, Xin Y, Chen K, Ding W, Wang Y. Sevoflurane-induced memory impairment in the postnatal developing mouse brain. Exp Ther Med 2018; 15:4097-4104. [PMID: 29731813 PMCID: PMC5920718 DOI: 10.3892/etm.2018.5950] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 03/06/2017] [Indexed: 12/28/2022] Open
Abstract
The aim of the present study was to confirm that sevoflurane induces memory impairment in the postnatal developing mouse brain and determine its mechanism of action. C57BL/6 mice 7 days old were randomly assigned into a 2.6% sevoflurane (n=68), a 1.3% sevoflurane (n=68) and a control (n=38) group. Blood gas analysis was performed to evaluate hypoxia and respiratory depression during anesthesia in 78 mice. Measurements for expression of caspase-3 by immunohistochemistry, cleavage of poly adenosine diphosphate-ribose polymerase (PARP) by western blotting, as well as levels of brain-derived neurotrophic factor (BDNF), tyrosine kinase receptor type 2 (Ntrk2), pro-BDNF, p75 neurotrophin receptor (p75NTR) and protein kinase B (PKB/Akt) by enzyme-linked immunosorbent assay were performed in the hippocampus of 12 mice from each group. A total of 60 mice underwent the Morris water maze (MWM) test. Results from the MWM test indicated that the time spent in the northwest quadrant and platform site crossovers by mice in the 2.6 and 1.3% sevoflurane groups was significantly lower than that of the control group. Meanwhile, levels of caspase-3 and cleaved PARP in the 2.6 and 1.3% sevoflurane groups were significantly higher than that in the control group. Levels of pro-BDNF and p75NTR were significantly increased and the level of PKB/Akt was significantly decreased following exposure to 2.6% sevoflurane. Finally, the memory of postnatal mice was impaired by sevoflurane, this was determined using a MWM test. Therefore, the results of the current study suggest that caspase-3 induced cleavage of PARP, as well as pro-BDNF, p75NTR and PKB/Akt may be important in sevoflurane-induced memory impairment in the postnatal developing mouse brain.
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Affiliation(s)
- Zhijun Lu
- Department of Anesthesia, Rui Jin Hospital Luwan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai 200020, P.R. China
| | - Jihui Sun
- Department of Anesthesia, Rui Jin Hospital Luwan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai 200020, P.R. China
| | - Yichun Xin
- Department of Anesthesia, Rui Jin Hospital Luwan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai 200020, P.R. China
| | - Ken Chen
- Department of Anesthesia, Rui Jin Hospital Luwan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai 200020, P.R. China
| | - Wen Ding
- Department of Anesthesia, Rui Jin Hospital Luwan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai 200020, P.R. China
| | - Yujia Wang
- Intensive Care Unit, Shanghai Jing'an District Shibei Hospital, Shanghai 200443, P.R. China
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Singh G, Singh V, Sobolewski M, Cory-Slechta DA, Schneider JS. Sex-Dependent Effects of Developmental Lead Exposure on the Brain. Front Genet 2018; 9:89. [PMID: 29662502 PMCID: PMC5890196 DOI: 10.3389/fgene.2018.00089] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 03/02/2018] [Indexed: 11/23/2022] Open
Abstract
The role of sex as an effect modifier of developmental lead (Pb) exposure has until recently received little attention. Lead exposure in early life can affect brain development with persisting influences on cognitive and behavioral functioning, as well as, elevated risks for developing a variety of diseases and disorders in later life. Although both sexes are affected by Pb exposure, the incidence, manifestation, and severity of outcomes appears to differ in males and females. Results from epidemiologic and animal studies indicate significant effect modification by sex, however, the results are not consistent across studies. Unfortunately, only a limited number of human epidemiological studies have included both sexes in independent outcome analyses limiting our ability to draw definitive conclusions regarding sex-differentiated outcomes. Additionally, due to various methodological differences across studies, there is still not a good mechanistic understanding of the molecular effects of lead on the brain and the factors that influence differential responses to Pb based on sex. In this review, focused on prenatal and postnatal Pb exposures in humans and animal models, we discuss current literature supporting sex differences in outcomes in response to Pb exposure and explore some of the ideas regarding potential molecular mechanisms that may contribute to sex-related differences in outcomes from developmental Pb exposure. The sex-dependent variability in outcomes from developmental Pb exposure may arise from a combination of complex factors, including, but not limited to, intrinsic sex-specific molecular/genetic mechanisms and external risk factors including sex-specific responses to environmental stressors which may act through shared epigenetic pathways to influence the genome and behavioral output.
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Affiliation(s)
- Garima Singh
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, United States
| | - Vikrant Singh
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, United States
| | - Marissa Sobolewski
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, United States
| | - Deborah A Cory-Slechta
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, United States
| | - Jay S Schneider
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, United States
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Raciti M, Ceccatelli S. Epigenetic mechanisms in developmental neurotoxicity. Neurotoxicol Teratol 2018; 66:94-101. [DOI: 10.1016/j.ntt.2017.12.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 11/28/2017] [Accepted: 12/04/2017] [Indexed: 12/28/2022]
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45
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Geier DA, Kern JK, Geier MR. A cross-sectional study of the relationship between blood lead levels and reported attention deficit disorder: an assessment of the economic impact on the United States. Metab Brain Dis 2018; 33:201-208. [PMID: 29134344 DOI: 10.1007/s11011-017-0146-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 11/07/2017] [Indexed: 10/18/2022]
Abstract
Attention deficit disorder (ADD) is characterized by a pattern of inattention and/or impulsivity that is inconsistent with developmental level and interferes with normal functioning in at least two settings. A recent meta-analysis suggested a significant relationship between lead (Pb) exposure and attention deficit symptoms. This study evaluated the potential relationship between increasing blood Pb levels and the risk of a reported ADD diagnosis. This cross-sectional study examined a sample of 2109 persons (32,762,158 weighted-persons) between 10 and 19 years-old from the 2003-2004 National Health and Nutritional Examination Survey (NHANES). This study analyzed demographic, socioeconomic, health related-questions, and laboratory tests using survey logistic and frequency modeling in SAS. On a microgram (μg)/deciliter (dL) basis, a significant dose-response relationship between increasing blood Pb levels and the risk of a reported ADD outcome was confirmed (odds ratio (OR) = 1.237, p = 0.0227). The relationship between increasing blood Pb levels and the risk of a reported ADD remained consistent when examining covariates such as gender, race, and socioeconomic status (OR = 1.292, p = 0.0301). Control outcomes selected on an a priori basis to not be biologically plausibly linked to blood Pb levels showed no relationship with increasing blood Pb levels. This NHANES analysis revealed an estimated 380,000 persons born in the United States (US) from 1984 to 1993 were reported to have an ADD outcome as a consequence of elevated blood Pb levels and the excess lifetime costs of these persons would be about US $100 billion. Every effort should be made to eliminate childhood Pb exposure.
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Affiliation(s)
- David A Geier
- Institute of Chronic Illnesses, Inc, 14 Redgate Ct, Silver Spring, MD, 20905, USA
- CoMeD, Inc., Silver Spring, MD, USA
| | - Janet K Kern
- Institute of Chronic Illnesses, Inc, 14 Redgate Ct, Silver Spring, MD, 20905, USA.
- CoMeD, Inc., Silver Spring, MD, USA.
- CONEM US Autism Research Group, Allen, TX, USA.
| | - Mark R Geier
- Institute of Chronic Illnesses, Inc, 14 Redgate Ct, Silver Spring, MD, 20905, USA
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Zhang XL, McGlothan JL, Miry O, Stansfield KH, Loth MK, Stanton PK, Guilarte TR. From the Cover: 7,8-Dihydroxyflavone Rescues Lead-Induced Impairment of Vesicular Release: A Novel Therapeutic Approach for Lead Intoxicated Children. Toxicol Sci 2018; 161:186-195. [PMID: 29029315 PMCID: PMC5837521 DOI: 10.1093/toxsci/kfx210] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Childhood lead (Pb2+) intoxication is a public health problem of global proportion. Lead exposure during development produces multiple effects on the central nervous system including impaired synapse formation, altered synaptic plasticity, and learning deficits. In primary hippocampal neurons in culture and hippocampal slices, Pb2+ exposure inhibits vesicular release and reduces the number of fast-releasing sites, an effect associated with Pb2+ inhibition of NMDA receptor-mediated trans-synaptic Brain-Derived Neurotrophic Factor (BDNF) signaling. The objective of this study was to determine if activation of TrkB, the cognate receptor for BDNF, would rescue Pb2+-induced impairments of vesicular release. Rats were chronically exposed to Pb2+ prenatally and postnatally until 50 days of age. This chronic Pb2+ exposure paradigm enhanced paired-pulse facilitation of synaptic potentials in Schaffer collateral-CA1 synapses in the hippocampus, a phenomenon indicative of reduced vesicular release probability. Decreased vesicular release probability was confirmed by both mean-variance analysis and direct 2-photon imaging of vesicular release from hippocampal slices of rats exposed to Pb2+in vivo. We also found a Pb2+-induced impairment of calcium influx in Schaffer collateral-CA1 synaptic terminals. Intraperitoneal injections of Pb2+ rats with the TrkB receptor agonist 7,8-dihydroxyflavone (5 mg/kg) for 14-15 days starting at postnatal day 35, reversed all Pb2+-induced impairments of presynaptic transmitter release at Schaffer collateral-CA1 synapses. This study demonstrates for the first time that in vivo pharmacological activation of TrkB receptors by small molecules such as 7,8-dihydroxyflavone can reverse long-term effects of chronic Pb2+ exposure on presynaptic terminals, pointing to TrkB receptor activation as a promising therapeutic intervention in Pb2+-intoxicated children.
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Affiliation(s)
- Xiao-Lei Zhang
- Department of Cell Biology & Anatomy, New York Medical College, Valhalla, New York 10595
| | - Jennifer L McGlothan
- Department of Environmental & Occupational Health, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, Florida 33199
| | - Omid Miry
- Department of Cell Biology & Anatomy, New York Medical College, Valhalla, New York 10595
| | - Kirstie H Stansfield
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York 10032
| | - Meredith K Loth
- Department of Environmental & Occupational Health, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, Florida 33199
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York 10032
| | - Patric K Stanton
- Department of Cell Biology & Anatomy, New York Medical College, Valhalla, New York 10595
| | - Tomás R Guilarte
- Department of Environmental & Occupational Health, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, Florida 33199
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Xu YL, Li XX, Zhuang SJ, Guo SF, Xiang JP, Wang L, Zhou L, Wu B. Significant association of BDNF rs6265 G>A polymorphism with susceptibility to epilepsy: a meta-analysis. Neuropsychiatr Dis Treat 2018; 14:1035-1046. [PMID: 29713173 PMCID: PMC5909779 DOI: 10.2147/ndt.s154927] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
INTRODUCTION Previously published articles have suggested that BDNF rs6265 G>A polymorphism is a potential risk factor for epilepsy. However, the results were not consistent. METHODS We conducted a meta-analysis to explore the association between BDNF rs6265 G>A polymorphism and epilepsy risk. Four online databases were searched, and related studies were reviewed from their inception up to June 20, 2017. ORs and corresponding 95% CIs were used to calculate the associations of each genetic model. Overall, 10 case-control publications involving 9,512 subjects were included in this meta-analysis. RESULTS Significant associations were found between BDNF rs6265 G>A polymorphism and epilepsy (A vs G: OR=0.88, 95% CI=0.83-0.94, P<0.01, I2=0%; GA vs GG: OR=0.88, 95% CI=0.79-0.97, P=0.01, I2=0%; AA vs GG: OR=0.79, 95% CI=0.70-0.90, P<0.01, I2=0%; GA+AA vs GG: OR=0.85, 95% CI=0.77-0.94, P<0.01, I2=0%; AA vs GG+GA: OR=0.85, 95% CI=0.76-0.95, P=0.01, I2=0%). Subgroup analysis also showed similar results in an Asian population. CONCLUSION Our meta-analysis indicated that BDNF rs6265 G>A polymorphism might be involved in epilepsy susceptibility, especially in the Asian population.
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Affiliation(s)
- Yue-Long Xu
- Department of Neurology, Linyi Central Hospital, Linyi 276400, Shandong Province, China
| | - Xiu-Xiu Li
- Department of Neurology, Linyi Central Hospital, Linyi 276400, Shandong Province, China
| | - Su-Jing Zhuang
- Department of Neurology, Linyi Central Hospital, Linyi 276400, Shandong Province, China
| | - Shi-Feng Guo
- Department of Neurology, Linyi Central Hospital, Linyi 276400, Shandong Province, China
| | - Jian-Ping Xiang
- Department of Neurology, Linyi Central Hospital, Linyi 276400, Shandong Province, China
| | - Long Wang
- Department of Neurology, Center for Evidence-Based Medicine and Clinical Research, Taihe Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China
| | - Lan Zhou
- Department of Neurology, Center for Evidence-Based Medicine and Clinical Research, Taihe Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China
| | - Bin Wu
- Department of Stomatology, People's Hospital of District Longhua Shenzhen, Shenzhen 518109, Guangdong Province, China
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Lewis BA, Minnes S, Min MO, Short EJ, Wu M, Lang A, Weishampel P, Singer LT. Blood lead levels and longitudinal language outcomes in children from 4 to 12 years. JOURNAL OF COMMUNICATION DISORDERS 2018; 71:85-96. [PMID: 29373108 PMCID: PMC5801000 DOI: 10.1016/j.jcomdis.2018.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 12/27/2017] [Accepted: 01/09/2018] [Indexed: 06/07/2023]
Abstract
OBJECTIVES In this study, the authors aimed to examine the association of a range of blood lead levels on language skills assessed at 4, 6, 10 and 12 years of age using a prospective longitudinal design controlling for potential confounding variables including maternal vocabulary, caregiver's psychological distress and symptomatology, child's race and prenatal drug exposure. METHODS The participants (N = 278) were a subsample of a large longitudinal study that examined the association of prenatal drug exposure on children who were followed prospectively from birth and assessed for receptive and expressive language skills at 4, 6, 10 and 12 years of age. Blood lead levels were determined at 4-years of age by atomic absorption spectrometry. A mixed model approach with restricted maximum likelihood procedures was used to assess the association of lead on language outcomes. RESULTS Longitudinal mixed model analyses suggested a negative effect of lead exposure on both receptive and expressive language, with the adverse outcomes of lead exposure appearing to become more prominent at 10 and 12 years. Higher caregiver vocabulary was positively associated with child's language scores whereas caregiver psychological distress appeared to negatively affect language scores. Prenatal drug exposure was not related to the effects of lead on language skills. CONCLUSIONS These findings suggest that elevated blood lead levels occurring early in life may be associated with poorer language skills at older ages. A language rich environment may minimize the negative influence of early lead exposure on language skills, with psychological distress seemingly exacerbating the negative outcome.
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Affiliation(s)
- Barbara A Lewis
- Department of Psychological Sciences, Case Western Reserve University, United States.
| | - Sonia Minnes
- Mandel School of Applied Social Sciences, Case Western Reserve University, United States
| | - Meeyoung O Min
- Mandel School of Applied Social Sciences, Case Western Reserve University, United States
| | - Elizabeth J Short
- Department of Psychological Sciences, Case Western Reserve University, United States
| | - Miaoping Wu
- Mandel School of Applied Social Sciences, Case Western Reserve University, United States
| | - Adelaide Lang
- Mandel School of Applied Social Sciences, Case Western Reserve University, United States
| | - Paul Weishampel
- Mandel School of Applied Social Sciences, Case Western Reserve University, United States
| | - Lynn T Singer
- Departments of Pediatrics and Environmental Health Sciences, Case Western Reserve University, United States
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Mitra P, Sharma S, Purohit P, Sharma P. Clinical and molecular aspects of lead toxicity: An update. Crit Rev Clin Lab Sci 2017; 54:506-528. [DOI: 10.1080/10408363.2017.1408562] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Prasenjit Mitra
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, India
| | - Shailja Sharma
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, India
| | - Purvi Purohit
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, India
| | - Praveen Sharma
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, India
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50
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Geier DA, Kern JK, Geier MR. Blood Lead Levels and Learning Disabilities: A Cross-Sectional Study of the 2003-2004 National Health and Nutrition Examination Survey (NHANES). INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2017; 14:ijerph14101202. [PMID: 28994742 PMCID: PMC5664703 DOI: 10.3390/ijerph14101202] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 10/06/2017] [Accepted: 10/08/2017] [Indexed: 12/15/2022]
Abstract
Difficulties in the acquisition and use of listening, speaking, reading, writing, reasoning or mathematical abilities are present among persons diagnosed with learning disabilities (LDs). Previous studies suggest a significant relationship between lead (Pb) exposure and LDs. This study evaluated the potential dose-response relationship between blood Pb levels and the risk of LDs. This cross-sectional study examined 1411 children (32,788,743 weighted-persons) between 6 and 15 years old from the 2003–2004 National Health and Nutrition Examination Survey (NHANES) by analyzing demographics, health related-questions, and laboratory tests using survey logistic and frequency modeling in SAS. On a µg Pb/dL basis, a significant dose-dependent relationship between increasing blood Pb levels and increasing risk of LDs was observed (odds ratio (OR) = 1.21, 95% confidence interval (CI) = 1.03–1.43). The relationship remained significant when examining covariates such as gender and race (OR = 1.19, 95% CI = 1.00–1.40). By contrast, no dose-dependence was observed between increasing blood Pb levels and the risk of hay fever in the last year (OR = 0.77, 95% CI = 0.56–1.056), a non-plausibly biologically related outcome of blood Pb levels. Persons in the 50th–75th (12.80%) and 75th–100th (17.14%) percentiles of blood Pb were significantly more likely to have LDs than persons in the 0–50th percentile of blood Pb (8.78%). An estimated 1 million persons born in the US from 1989 to 1998 developed LDs from elevated blood Pb levels. Overall, this study revealed a significant dose-dependent association between increasing childhood blood Pb levels and the risk of a LD diagnosis, but it was not possible to ascribe a direct cause-effect relationship between blood Pb exposure and LD diagnosis. Childhood Pb exposure should be considered when evaluating children with LDs, and continuing efforts should be made to reduce Pb exposure.
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Affiliation(s)
- David A Geier
- Institute of Chronic Illnesses, Inc., 14 Redgate Ct, Silver Spring, MD 20905, USA.
- CoMeD, Inc., Silver Spring, MD 20905, USA.
| | - Janet K Kern
- Institute of Chronic Illnesses, Inc., 14 Redgate Ct, Silver Spring, MD 20905, USA.
- CoMeD, Inc., Silver Spring, MD 20905, USA.
- CONEM US Autism Research Group, Allen, TX 75013, USA.
| | - Mark R Geier
- Institute of Chronic Illnesses, Inc., 14 Redgate Ct, Silver Spring, MD 20905, USA.
- CoMeD, Inc., Silver Spring, MD 20905, USA.
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